said about "pedestals the better. The Great Northern Railway had better look out, or they may be beaten on their own ground. In the letters of "S. T." and "W. E. H." (letters 11365 and 11369, p. 592) reference is made to Mr. Walton's evidence; he is, however, only passenger superintendent, and his evidence as to speed is not reliable. It was contradicted by the statement produced at the time, and I know it to be incorrect. I am very much interested in this discussion, but I wish we could get rid of some of the party spirit manifested. We don't want Great Western Railway or Midland, or any other advocates, but we want as much information as possible. I don't suppose there is any engine that will beat every other; and after all, that is hardly the point. Each line rather wants the engine best suited

[11483. ALLOW me to correct three typographical errors which appeared one in each of three squares I sent (letter 11382, p. 594). The fifth term in the fifth horizontal row from the top (first square) should be 35, not 36. The second term in the fourth row (second square) should be 20, not 23. And the last term in the third square for 37 read 36.

I now, according to promise, send what may be called the multi-magic square from 1 to 256 terms, which contains 16 perfect smaller squares of 16 terms each, thus affording 191 exercises in addition. I think the most simple square to do is one with 16 terms, say from 1 to 16. All you have to do is to write down the terms in their regular order, and then reverse the two diagonals, when the square will be perfect. See the last group of 16 terms contained in the accompanying square. Then take the next 16 terms, from 17 to 32, and square them likewise; and so on till you have completed 16 squares, and these squares similarly arranged will complete a large square. I will, with your permission, on a future occasion send an easy method of constructing squares with 36, 64, and 100 terms each respectively, which I consider are found at present to be the most difficult in constructing

PURE WATER AND FILTERS. [11491.-"BEAUJOLAIS'" plan (letter 11408, p. 613) for obtaining pure water is a very good one, but I have seen a modification of it I think better. Instead of a small in. pipe used as a worm im. mersed in cold water to condense the steam, I prefer a larger pipe (say of 3in. or 4in. diameter) exposed to cool air, which, with a pipe 8ft. or 10ft. long, will condense a considerable quantity of water, probably enough to drink and cook with; and condensation may be helped by covering the pipe with blotting paper kept wet; but when I saw it in use enough water was condensed without that. The larger pipe costs more, but there is no need of tub and change of water. If the water contains organic impurity, a little of Condy's fluid may be put into it.

I do not agree that filtration is useless, for espe cially intermittent filtration renders water tolerably good quite wholesome. It does much more than strain out suspended solid matter, for when a porous filter is alternately wet and dry it forces into close contact organic matter with the oxygen of the absorbed air, and if the quantity of the former is not great may insure its entire decomposition. It is, of course, less certain than distillation.

[11489.]-THE letter of "B. H., Solr.," (11412) induces me to ask if the following suggestions are practicable:

1. A roller skate with any number of rollers in the shape of cup and ball joints. The diagram Fig. 1 will explain what I mean.

2. A roller skate with any number of "castors" (those known as "direct-bearing," by preference), the same as used for chairs, sofas, &c.

3. A combination of fixed wheels, with either the cup and ball or direct-bearing castors. The wheels with fixed axles would of course be in front. With regard to the castors, the "twisting" movement would, of course, be confined to a few degrees, sufficient to enable a skater to turn in as

Sigma," as a teacher of political economy, course cannot be mistaken in a point of so much importance, so I venture to ask him if he will oblige me by stating where the line is drawn between little

estates, which I know, at the cost of some hundreds of 1ounds, are liable to the tax on inheritance, and the large estates which "Sigma" says are exempt from them. I ask merely for information, as I have

carefully read the Act (16 and 17 Vict., cap. 51), and that makes no distinction between large and small landed estates, but charges them all with the same duties, varying from 1 per cent. to 10 per cent., according to the relationship of the successor to the predecessor.

I cannot suppose that "Sigma," writing with so much authority, is ignorant of this Act, passed more than twenty-three years ago, and, therefore, I conclude that his profound researches have made him acquainted with a subsequent Act, which has escaped my rather superficial observation. In any case I shall be glad of his explanation. F. W. M.

FRIEDMANN'S PATENT INJECTORS. [11496.]-SOME of your corespondents have asked for drawings, and also rules, for working the Friedmann's injectors. As, up to the present time, these have not been given, I hope the sketches and short description may be useful to your readers. I may remark that there are two classes of these injectors in use upon locomotive engines. The first, or class "A," which is non-lifting, must be placed below the lowest level of the water in the tank. The second, or class "B" is lifting, and can be placed either on the level with or above the water tank. In this present letter I will confine myself to the description of the first, or class "A." Referring to the draw. ings, Figs. 1 and 2 show the arrangement of the injector upon a locomotive. I have selected a drawing where the injector is outside, as it shows it more clearly; but they are frequently placed under the foot-plate, as on the Midland engines. Figs. 3 and 4 show the elevation and longitudinal section. Fig. 5 is the cross section of the overflow valve, "K." It will be seen from Fig. 4 that the injector is very simple in construction, having no stuffing boxes or

CLASS A.-As long as the injector is inactive, the
overflow valve, K, and the steam valve, F, to be kept
closed. The water-cock, D, is always left open.
TO START.-Open the overflow valve, K, far
enough to allow a play of to of an inch, and then
open slowly the steam valve, F. If, after opening
the steam valve full, the discharge of water out of
the overflow still continues, turn the water-cock, D,
slowly off till it does stop; and the cock then to be
left in that position.

TO STOP.-Shut the steam valve, F, and then the
overflow valve, K.

To WARM THE WATER IN THE TENDER. Shut the overflow valve, K, and open the steam valve.

The temperature of the feed-water not to exceed
122 Fah.; at this temperature it is delivered into
the boiler-nearly boiling.

TO STOP WARMING.-Shut the steam valve, F,
and open for some seconds overflow valve, K, to cool
the injector by the water flowing through the same,
then shut overflow valve, K, again.
August 21st.

C. E. S.

SELECTED CORRESPONDENCE.

WAR TO THE KNIFE."

THE Cruelty to Animals Act, which has just been issued in its final shape, does not seem quite so abortive a measure as the reports of it in the newspapers made it appear. The poeans of the British Medical Journal which last week 66 congratulated the profession" on its passage, in an article which the Times thought worthy of quotation, were possibly prompted by the desire of the editor to leave the field with a flourish of trumpets, to prove (as he complacently remarks)" how great power our profession possesses when united," &c. (as we may add), when led to war by a captain reflecting upon it such exalted honour. Making the best of it, however, the Act is thoroughly unsatisfactory, viewed in any other light than as a basis for future legislation, and a means of testing how many learned authorities will certify that totally superfluous experiments are indispensable, and how far a Secretary of State will presume to judge whether a gentleman of Dr. Klein's Sonority of Various Metals.-M. Decharme opinions is a proper person to receive a license. Any has been studying the comparative sound-power of way, I apprehend that every license taken out must various metals. His experiments were made on necessarily in some way be published (or how are cylindrical rods, 2 decimetres in length, and 1 centi- magistrates to know whose premises they may not metre in diameter, suspended by thread, or sup- search ?), and thus we shall be able henceforth to ported on the edges of cork prisms. The rod was recognise, with all the respect they deserve, our struck at its centre with a wooden hammer covered Sworn Tormentors." To suppose that the agitation with indiarubber. The minimum number of vibra- of the question can stop at this point is, of course, tions (690) was given by lead, the maximum (2762) absurd. It only remains to be considered what form by aluminium; the intermediate numbers, neglecting the movement should now assume. In my humble fractions, were:-Gold, 976; silver, 1034; tin, judgment, the efforts of the party who aimed at a 1161; brass, 1303; bronze, 1381; zinc, 1422; cop- moderate compromise, having been met with per, 1642; cast iron, 1843; wrought iron, 2192; unqualified opposition, there remains nothing for as steel, 2322. The duration of the sounds was in the to do but to denounce the practice of vivisection following proportions (in seconds) :-Lead, 03; tin, altogether. Had we been able to reconcile the claims a little less than 10; zinc, 1; cast iron, 20; cop- of science and humanity, we should have greatly per, 5; wrought iron, 12; brass, 14; bronze, 24; rejoiced. But since science refuses to admit the

steel, 45. The sound produced by steel placed on
the cork prisms lasted only 25 seconds, not more
than half the time of its duration when suspended by
a thread, and struck in the same way in each case.
Bronze, on the contrary, gives a sound lasting 25
seconds on the cork, against 24 when suspended.

claims of humanity, we have no hesitation in letting science go to the wall, and vindicating, to the utmost of our power, the nobler principle.

other moving parts, all the nozzles being fixed. Therefore it is perfectly easy to manipulate. It will start working without the least trouble, and also feed clean-that is, without losing any water out of I venture to lay before your readers, for their conthe overflow. "K," up to a temperature of 122 sideration during the present interval of rest, the Fah.; but, if the heat of the water exceeds 130°, expediency of forming an anti-vivisection league, to some will be lost out of the overflow, K. Many locomotive superintendents have objected to the use Fenugreek.-A recent number of the Gardeners and Irish-having for their object simply to put consist of a federation of societies-English, Scotch, of two injectors upon an engine, and have preferred Chronicle contains a good description of fenugreek, down vivisection. A central committee should meet one injector and one pump, partly on account of the a drug whose therapeutic value has never received weekly in London, and the honorary secretaries, waste of steam and water at starting, and also that adequate appreciation. It might fairly be imagined one or two, and delegates from each of the local sometimes those with moveable nozzles have failed on that its administration would prove beneficial in societies, should have a right to sit on the committee a journey; and I have myself known several cases of certain wasting diseases. At all events it is given when they come to town, and on all important the old injectors failing, and drivers having to pull in many parts of the world to produce fatness-a occasions. their fire out to save burning the engines. But the result which it accomplishes with marked success. Friedmann injectors, being perfectly easy to work, Readers of Dr. Leared's "Morocco and the Moors " The method of work adopted by the society, I and certain in their action, are largely used on locothink, should be regulated by the fact that, as we motive engines. They generally have two numbers, may remember that the seeds are taken by women have been defeated in our efforts to make cruel 7 and 9. By regulating the water-valve, D, the in Morocco to induce embonpoint. The genus to vivisection illegal, we must endeavour to make it capability of the injector can be made exactly to which the fenugreek belongs is pretty widely distri- infamous. We should, therefore (1), obtain and supply the boiler with as much water as the engine buted in Southern Europe, Northern, Central, and publish all possible information respecting the consumes, so that it is only necessary to stop and Southern Africa, Western and Central Asia, while licenses and certificates granted under the new Act, start it at long stoppages. Upon page 362, in the it is said that one species is found in Australia. dimensions of a Midland engine which I gave, two Fenugreek claims a history of great antiquity the Friedmann's injectors are used. plant being much valued by the ancients both for The following table will show the number of food and medicine, and being often referred to by gallons each injector can deliver per hour into the Hippocrates and Pliny, the latter of whom enters very fully into its medicinal virtues. Woodville, in Medical Botany," refers to the plant as a SIZE, THAT IS DIAMETER OF RECEIVING NOZZLE native of Montpellier. Southern France and Germany furnished this country with its supplies of 2 3 4 5 6 7 8 9 10 fenugreek-seeds at the time Woodville wrote. The plant is now largely cultivated in India, Morocco, 88 192 350 540 770 1,060 1,400 1,760 2,150 of food during the germinating stage. In India the &c. In Alexandria the seeds are eaten as an article Delivery per hour in gals., at 45lb. steam pressure: fresh plants are eaten as a green vegetable; but the 57 128 228 351 514 700 910 1,157 1,428 seeds are the most important product, as proved by recent statistics, which show that the quantity imDelivery per hour in gals., at 201b. steam pressure: ported from Said to Bombay during the year 1872-73 40 88 180 215 350 480 650 800 amounted to 13,646 cwt.; from Bombay also were shipped in the same year 9,655 cwt., of which Subjoined are the rules for working these injec- quantity only 100 cwt. were sent to the United Kingdom.

boiler :

IN MILLIMETRES :

Delivery per hour in gals., at 120lb. steam pressure:

tors:

980

his "

the names and addresses of the persons receiving them, and details of their experiments past and present; (2) we should employ lecturers, and hold meetings, large and small, throughout the country, perhaps including an open-air meeting next spring in Hyde Park; (3) we should do our utmost to disvivisection in the medical schools attached thereto; courage all hospitals whose authorities sanction (4, and lastly) the members of the league should pledge themselves, in the way proposed by the Home Chronicler, to employ, preferentially, medically and suggestion has been condemned by some of our surgically, the opponents of vivisection. This last friends, but, I think, unjustly. I would not go to a shop to buy stolen goods: I will not consult a doctor who will sell me knowledge obtained in a way which I deem far worse than robbery.

There should be a secretary of the league-a competent physiologist, with sufficient salary, and also

* From the Home Chronicler.

travelling lecturers, to be engaged by the local
societies in succession.

Further details should be worked out by the
gentlemen and ladies who might be willing to under-
take the promotion of the scheme.

Dolgelly, August 22nd.

Frances Power Cobbe.

REPLIES TO QUERIES.

**In their answers, Correspondents are respectfully requested to mention, in each instance, the title and number of the query asked.

more.

64

SEPT. 8, 1876.

accompanying the above work afford a ready means of reference for those who are unable to get evidence, which is quite definite, and offered by men 'subjects." I am willing to abide by the above who, perhaps Mr. Hugh Clements' will deign to believe. Our readers may settle the matter for themselves whenever an opportunity occurs to them THE STEWARTON SYSTEM AND THE [26200.]-Sea-Water Condenser. I suppose their own. The teeth of the rudest grossest, most for comparing the teeth of a cat and a monkey with "Condenser STEWARTON HIVE.* been at sea for a short time with them, but I cannot are those of the highest chimpanzee. Many animals means a surface condenser. I have perverted class of men are less fit for tearing than THERE are many bee-keepers like myself who keep surface condenser of a marine engine is a cast-iron their constitution. Sheep can exist on fish, &c.; a few hives to supply their household and their casing, filled with brass tubes, about outside dia- while they do so, though they are practically say that I thoroughly understand" them. friends with honey, but do not care to have a large meter, and are only thin; they are fastened into carnivorous, constitutionally they are herbivorous, A besides man can exist on food not in accordance with number of stocks. They generally follow the non- brass plates at each end with wooden ferrules. and are living at a disadvantage. Man may be the swarming system, and prefer a moderate amount There are other ways of fastening them; but I have paragon of animals, but some members of his kind of super honey in the comb to any amount from a only seen the wooden ferrules used. stock hive; but in spite of all their efforts their bees condenser is so arranged that when the water is let they talk high and off-handedly about this and that will swarm and increase their stocks beyond the in from the sea it goes on the top (if it be a horizontal Quite seriously I have been hoping that vegetarians The surface cannot argue worth a brass farthing, even though required number, and at the end of the season give one), down one end, through the inside, out of the were on the way to do man a good turn by alluring them just what they do not want-namely, the other end, then is drawn away with circulating him towards arbours, &c.; but Hugh Clements trouble of driving, uniting, and, worst of all, break-pump, and put back into the sea. When the steam would have me believe that this prospect of elevation ing up stock hives and running honey. In many tubes, and other cold surfaces, is there condensed, a monkey, and that for man to maintain or surpass cases no doubt the bees are condemned to the sulphur and is drawn off with the air-pump into the hot-well; his present noble position he must stick by the is exhausted into the condenser it rushes on the cold is an illusion; that I am more like a hog than like pit. My own system is to prevent my stocks from the feed-pump then puts that which is condensed slaughter-house and take a turn at tearing out a piz's multiplying unduly by uniting a number of swarms. back into the boiler.-FRANCOIS. By this method I also get my deserted supers filled as well as others besides. It is not every one who cares to add swarm to swarm says of adularia or moonstone that it is a variety of original distribution was tropical, or nearly so, are [26210.]-Moonstone.-" Jackson on Minerals' heart, &c., &c. Is he fooling? Fie on such fooling! in the ordinary way of knocking them out in the flection of pearly light comes from Ceylon. This is climate for my own living in. The 750 miles' march The reasons why I should expect to find that man's evening and placing the hive to which they are to be the fact. I myself have had handfuls, so to speak, done in eleven consecutive days was done on parched felspar, and that the variety remarkable for its re-identical with those I gave for preferring such a added over them, with the trouble of placing all right offered me there at a few pence a-piece. Cood ones corn. Smith's " early next morning. To these let me recommend the-that is, those with the pearly reflection, properly 2nd Edition. The same author, page 167, gives the Stewarton system of adding swarm to swarm. simply to hive the swarm to be added to another in a It is situated, and a full-cut en cabochon-are worth following account of one of the Smyrna porters, who Fruits and Farinacea," page 174, hive or box constructed with bars. with moveable 03 by 02 across perfect ones for 3s. 6d. a piece, 400lb. to 8001b., and live on coarse bread, firs slides between the frames like the Stewarton hive; selected out of many hundreds. Chapman, in his grapes, or raisins :-"He carried at one load, from I bought in London some few years ago three habitually, when working, carry on their backs from or, which will answer as well, a flat board or sheet of zinc, which can be withdrawn and placed over the silica, 64 20, alumina, 13:40, potassa, 16'95, as Practical Mineralogy," gives (p. 92) for adularia, his warehouse to the wharf, about 25 rods (137yds.), pars. A cheese box perforated with a sufficient Berthier's analysis. It is fusible into a white jelly two sacks of coffee weighing each two hundred number of slits or fitted with bars would answer well glass, specific gravity 25 to 28. It would, therefore, he pounds, making, in all, eight hundred pounds; that, a box of sugar weighing four hundred pounds, and for round hives. ever, that one would have thought it would be stopped and requested that another sack of coffee easy to detect an imitation. They are so cheap, how- after walking off a few rods with a quick step, he hardly worth while to imitate it, and I rather doubt might be added to his load." charming stone when properly treated by the lapi- have already, in the case of the Hindoos, instanced if it could be easily imitated successfully. It is a dary; but generally they are cut so flat as to be of a race of men that are completely frugivorous. I term frugivorous was meant to include farinaces, Į Premising that the less than 4th above its girdle. The back may be flat not mentioning that farinacea should be so included. or a little rounding.-A. I. C. E. no value. A stone in. diameter should be not much apologise to those readers whom I have misled by the effect I wished to produce. There is much better material awaiting circulation than what I know, vegetarianism includes more than cabbages and that To prevent a somewhat similar error I now say that and what I know is of more importance to our readers than what I think; therefore, I am inclined sort of thing. The above omission will not impair to be cross when asked whether I really think Newton's Principia' is any better than it would have been if he had written it under a mixed could not possibly have been the quiet, patient, effective worker he was, unless he had been so unregimen." I really think that it is. I think Newton perverted that he could, in some degree, profit by the still further increase his serenity and power. The advantages offered by a diet in harmony with man's I will now ask questions: 1st. Is the Stewarton which their vegetarian ancestors won. constitution, and therefore a vegetable diet would hive generally managed on the swarming or nonmeans will Mr. Hugh Clements maintain his asser become carnivorons, and they certainly lost that Romans were probably the same breed after they had swarming system, or on both? By both I mean-Is the non-swarming system aimed at, and the other accurate" when I said that "starch is changed in tion "that the mental energy of By what stocks swarm against the will of the owner? 2nd. that when I eat good bread I taste something sweet. Considering the item of bilious attacks alone vege the mouth into sugar." I am ready, but not regimen ?" Is the ordinary octagon Stewarton hive, or some I have hitherto accepted the explanation afforded tarianism during the last nine years has conduced to modification of it, the most useful? 3rd. What is parts each Gin. deep, instead of in one whole 12in. the object or advantage of having the stock boxes in deep? Would not one stock box 12in. deep, with 6in. nadir, in case additional room was required below for breeding and for uniting, answer equally well? 4th. What is the object of having the supers only 4in. deep? 5th. What is the advantage of placing the additional super when required on the top of the partly filled super instead of underneath it, it being a common opinion that bees prefer working downwards, and are more eager to fill an interval of space, whereas they frequently refuse to ascend into an empty super?-Ò. B.

The swarm is hived in this prepared box, placed as near as possible to that to which it is to be united, or merely left where it was hived till the evening, and at sunset placed gently beneath the hive to which it is to be united, and the slides or cover withdrawn, whereupon the new swarm will set up a pleasant hum, a sign that they are gladly joining their neighbours in the upper story. The next morning the bive underneath may be removed, and the partially filled super deserted by the swarm placed on the top of the united stocks. A third swarm, if not too large, say a cast, may be added and additional room given above if the season be not too far advanced. One hive thus treated has given me two fine supers, one 15lb. and the other 12 lb. I have thus been led to think that for many amateurs the Stewarton hive will be found far the most easy to manage, and will also afford the most satisfactory results. At any rate, with it stocks can be kept within the number desired, and a large ing-up of stock hives with all its abominations amount of super honey made sure of, and the break

avoided.

a

solid food, on entering the mouth, is masticated or
broken up into minute portions and mixed with the
[26257.]-Animal and Vegetable Food.-"The
saliva, swallowed, and mixed with an acid juice
poured into it on its entrance into the stomach, the
liquid (the gastric juice) flowing out of its walls.
Here the proteids are more or less dissolved and
absorbed by the veins of the stomach, also so much
of the starch of the food as has been under the in-
fluence of the saliva converted into sugar."-Angell's
"Physiology," page 116, 1873. "As the food is masti
cated by the teeth saliva is poured through the gland
ducts into the mouth and becomes mixed up with
starchy portions of it are converted into sugar.
the broken-up part of the food, by which means the
Hugh Clements to afford us the means of estimating
This process is termed insalivation.'
the value of his assertion that I was "not quite
"Physiology," page 62, 1873. I should like Mr.
Piller's

to accept a more reasonable explanation of the fact

would

flesh

my effective working power more than enough to considerable obligation to Dr. T. L. Nichols, who compensate me for the petty inconveniences due to first aroused my interest by asserting that " eating physiologists and physicians, I know, have prejudice there are no others-and placed me under contended for the necessity, if not the beauty, of eating animal food; but all' experience, all science, and all philosophy, are arranged against them."

assertion has become more credible the more I have
examined it or seen it examined.—ENOCH EVANS.
Mysteries of Man," page 226, 1867. The above
troversy from
[We have received contributions on this con-
A. Edwards, "Saul Rymea,'
Toothsome,'
Academician," F.
"A Vegetarian," and

66

above. I knew, when I wrote before, that, if starch the intestines. My best reply to Mr. Hugh Clements' be not insalivated as it should, much of it passes into remarks respecting the death of Mr. Lancaster, Dr. Carpenter's testimony, the diet of Greenlanders, and the advisability of making a gradual change, will be to respectfully advise a re-perusal of those portions of my letter on page 596 which are related to the foregoing items. I regret that Mr. Hugh Clements should have equalled, if not excelled, the vulgar "mixed diet" differences which separate man from the chimpanzee blunder. and gorilla are great and significant." Alas for the "The structural cogency of Mr. Clements' argument! The significance is wholly in favour of vegetarianism, being such as to indicate that man's constitution differs" J. H. J." for which we are unable to find room. Huxley, in speaking of the four genera of anthropo- pretty well discussed in our paper. more from a carnivorous one than a monkey's does. The question has, however, from time to time beep morphia, in relation to man, says: "The chimpanzee Evans may quote Prof. Owen or a hundred Prof. approaches most closely in the character of its Owens: the people of to-day will do very much as cranium, its dentition, and proportional sizes of its they did yesterday. If an archangel were to proclaim Mr. Enoch arm.' connection with the skull I may speak of the teeth-say that by eating fruit his grandfather caught a -Vertebrated Animals," page 487, 1871. " In that man by nature was frugivorous, some one would of men had a narrow escape. One-rail Railways.-While the war of the succession, when as a whole, are usually regarded as organs which have a peculiar classificatory value, cold and died, and therefore he ought to eat pig as gauges goes on, a road has been commenced in more trustworthy indicators of affinity than any such ages with a shudder. and of whose differences of number, form, and well as fruit. During the darker ages men fed on California that is clearly out of the controversy, for others."-Huxley's "Man's Place in Nature," page infamies recently perpetrated by half-savage Asiatics it has no gauge at all. In other words it is to be an 81, 1864. Professor Owen says: men. Time passed away, and we now look back on experiment with the one rail, or prismoidal, system, monkeys, which man most nearly resembles in his infamies two or three thousand years ago, as is to connect the town of Sonoma with a steamboat dentition, derive their staple food from fruits, grain, abundantly evident from Bible and Pagan history; The indescribable "The apes and in Bulgaria would not have been regarded as landing. If it proves successful, it may turn out the kernels of nuts, and other forms in. which the They were then regarded as the Right Hon. Ear! that this peculiar plan will meet with considerable most sapid and nutritious tissues of the vegetable Beaconsfield, Prime Minister of England and Lord use for local roads, and especially where expensive kingdom are elaborated; and the close resemblance Privy Seal, regarded them a few weeks ago, as engineering would be necessary for the ordinary between the quadrumanous and human dentition ordinary incidents of civil war. shows that man was, from the beginning, more especially adapted to eat the fruit of the trees of the and looks upon such matters man is Semitic in origin and Asiatic in sympathy, But that gentlegarden," "-"Odontography," page 471. The plates light from that in which in a different they are

Explosion of Dynamite. At the Albion Works, Sheffield, on Monday, an explosion of dynamite, used for the purpose of loosening iron at furnace bottoms, occurred, hurling a quantity of metal a distance of 500 yards across two streets and into the road of the Cyclops Works, where a number

rond.

From the Journal of Horticulture.

regarded

SKPT. 8, 1876.

by the upstart nations of Western Europe.
Possibly, in the other and, we hope, the brighter
to come soon, the systematic
ages that are
slaughtering of men by scientific means on the battle-
field will be looked back upon with wonder and pity,
But that such ages will come is pretty certain, and
when they do come that higher and purer and holier
life advocated by vegetarians will probably be
realised. It is a source of high satisfaction to know
that in this war-blasted world humanity advances
with an undying capacity for improvement, and that
before it lies a limitless future.-ED.]

[26429.]-Boiler Pump.-I cannot account for your vacuum under the suction valve, unless it is that by mistake you have fixed the suction pipe to the top of the air pump, instead of the hot well, or there is something lodging in the pipe, or the discharge valve in hot well lapping over the inlet. Does the water run freely through when you take out the suction valve? If all is right, it ought to do so. If the above suggestions are not correct, take the suction pipe off, and try a wrought-iron one, bent as a siphon, over the top of hot well. See that there is no leak about the top of your pump. If the packing is small for your stuffing-box, and the bottom bush slack, you might be drawing air that way. Also see your discharge valve is not hinging up. Persevere, and you will succeed.

ASSISTANCE.

[26443.]-Sweet Toned Harmonium.-I fully comprehend Mr. Fryer's statements, but I do not understand why he should persist in his attempt to introduce confusion. If the "French" reed is to be called English because made in this country, what will be call the American reed when that is made here? English too, I suppose. The real English reed is, of course, Wheatstone's, but I never heard of it being used in harmoniums. "A man's not a horse because he is born in a stable," nor does German silver when cast in Clerkenwell become English silver. If by "inferior" Mr. Fryer means that one of Alexandre's lower-priced instruments has not had the care bestowed on it that the dearer ones have, I can agree with him, but any amateur who can build his first harmonium equal to one of Alexandre's so-called "inferior," may rest contented. As to the pans, Mr. Fryer puts it the wrong way when he says that "pans made entirely of pine belong to the inferior class of pans." In ferior pans are made of pine because that is the cheapest wood; but there is no reason why first-rate pans should not be made of pine. As there may be some misconception on this point, it may be as well to say that there are two kinds of pans: those bored out of the solid and those built up. I suppose solid pans are generally made of beech because there is less liability to spoil them in the making than there would be with pine; though in America, where pine is cheap, tube-boards are made out of that wood solid. But many of the very best instruments made in England have built-up pans, with channel frames and divisions of pine, and beech veneers, the latter, I suppose, because they tend to prevent warping, and because screws hold better in thin beech than in thin pine. It is obvious that whatever advantage in the way of resonance is to be gained from the mere choice of wood for the pan, pine will not suffer when compared with beech. Perhaps Mr. Fryer will now supply the description. I note that he does not say anything about the "volume" of his instrument, which, I have before hinted, was probably equal only to that of an organ accordion.SAUL RYMEA.

man

[26507.)-Preserving Brightness of Brass Wire and Preventing Verdigris.-Let Country: try lacquering his brass wire. I think it will I know a pair of scales, suit his purpose well. lacquered about 18 months ago, as bright as when first turned.-H. L. CRATE.

[26514.]-Tennis Bats (U.Q.).-Ash is used. Can be bent to shape by steaming or boiling it till soft. I have put new gut on several, and found no difficulty in pulling it as tight as I wished; but it might be an advantage to damp it first, as it will shorten as it dries.-J. B., Belfast.

"Frenchman" [26629.]-Speed of Bicycle. may surely take it that no one has yet ridden 50 miles in 2 hours 20 minutes on a bicycle, and never will if his own legs are to propel him. Bicycles with driving wheels of 7ft. have connecting rods and treadles which work on guides. The large size of wheel of course assists in covering the ground, but the extra friction discounts this advantage so much that practically there is no advantage in having a larger wheel than one the treadles of which can be reached with the feet.-S. MAYER.

[26656.]-Fly-wheel for Lathe.-"C. A. T." gives a sketch of a friction wheel for the above. I have seen such a thing working, but the main shaft rubs heavily against one of the uprights, although it does work comparatively easy. I send a sketch of one which I mounted about 35 years ago, and I do so because I think it is much better than "C. A. T.'s." Fig. 1 is the plan, Fig. 2 is a side elevation; the letters in both refer to the same parts. A fly-wheel shaft, 2 in. diameter; B B friction wheels, 3in. diameter and 1in. broad; C C friction-wheel axles, in. diameter, cast-steel hardened and fixed into wheels; DD cast-steel plates in. thick, and hardened after being bored to receive axles of friction wheels; E is a cast-iron box or casing, holding steel plates in proper position, and also containing oil. The steel plates are put on to the axles of friction

wheels, and all are made a good fit and dropped into
the cast boxes, which are then filled with good oil as
far as to touch the lower parts of friction wheels, and
as these revolve the oil trickles down their sides, and
thus lubricates their axles; a cover is put on to keep

out dust. I may mention the fly-wheel is 6ft.
diameter, has a wooden pulley fixed to side of arms
for strap or bands; weighs over 6cwt., and has been
worked for months without adding more oil.-AN
OLD MECHANIC, No. 1.

[26693.]-Magic Lantern Photographs.-To
MR. LANCASTER.-As I am not fortunate enough
to have the volumes of the MECHANIC in my posses-
sion, I shall esteem it a great favour if you will give
me full and simple instructions how to proceed.-G.
FRYER.

[26713.] Red Ink.-Saffranine CH2N4. This
body is a derivative of pseudotoluidine, and is
obtained by treating high-boiling commercial aniline
first with nitrous acid, and then with arsenic acid,
or other oxidising agents. The hydrochloride
CHNCIH occurs in commerce in the form of a
paste or reddish powder. It is very soluble in water,
but not in a solution of salt, and dyes on silk most
delicate rose tints. It is, therefore, largely used as
a substitute of safflower. It dissolves in concentrated
sulphuric acid with a splendid green colour. On
gradually adding water to this solution, the colour
changes successively into greenish-blue, blue,
purple, violet, and finally red.-KINO.

[26713.] Red Ink and Saffranin.-For the
benefit of our readers in general, and "Dædalus"
in particular, I give the following facts concerning
Saffranin:-It is one of the coal-tar products; is
used as a red dye, and has the formula C2HN. It
is prepared commercially by treating the higher boil-
ing portions of aniline oil with nitrous acid and arsenic
acid successively. Chromic acid has also been used
with advantage as the oxidising agent instead of
arsenic acid. It is met with in commerce either in
the form of a paste or as a yellowish red powder, in
which the saffranin exists as the hydrochloride, fre-
quently mixed with calcic carbonate and salt. The
base may be obtained in the free state by decom-
posing this hydrochloride with argentic oxide. On
evaporation of the deep red liquid it is deposited
in reddish brown crystals on cooling. It is easily
soluble in water or alcohol. On the addition of
strong sulphuric acid to a solution containing it, the
On dilution the same
colour changes to a fine violet, passing to blue, dark
green, and light green.
changes of colour take place, but in an inverse

order.-MAC DANDARTS.

[26713.] Red Ink.-Saffranine is made from
aniline nitrate (which is prepared by passing
into aniline the vapours evolved from a mixture of
starch and nitric acid); the product is washed two
or three times with water, and then treated with
half its weight of arsenic acid to 80-120° C. for
five minutes. The product is poured into boiling
water, and lime added until the acid is neutralised.
The liquid is then filtered through flannel, and the
colouring matter salted out from the clear red liquor
The pasty mass is then drained and
by means of common salt (5 parts to one of aniline
nitrate).
pressed to remove the brine.-H. B. ROSTRON.
[26717.]-Liverpool Dry Plates.-I have had
about seven dozen of these plates this season, and
have not found one spotty. Certainly the latter end
of last year they sent out some plates that were in
very bad condition, but this year they seem to have
both made them more sensitive and with more care.

I think, if Mr. Lancaster would try another batch,
[26720.]-Marsh's Vibrating Electric Wire.-
he would quite alter his opinion.-JUSTICE.
You will succeed in working this experiment by using
hard drawn and the coils about lin. or 1fin. diameter,
a coil of naked copper wire, No. 24. It should be
and as close as possible. The end of the spiral
should only just graze the surface of the mercury.
I have one working now with a current from a
battery of 4 cells-Grove's-but 6 would be better.
If you have any further difficulty write again.-
G. R. P.

[26743.]-Electrical.-To W. J. LANCASTER AND "OLD TOTTLES."-Thanks for answers to first and third questions. I meant the second one to have been, "Is there any way of reversing the poles of a permanent magnet from north to south, and vice versa, either by electro-magnetism or in any other way? My reason for asking was because I have repeatedly changed the poles of the needle of a mariner's compass without touching the needle. I do not understand about quantity, and should be glad to have it explained.-ARTHUR ADAMS.

[26750.]-Tonic Sol-fa Notation.-As I am a staunch advocate for Sol-fa Notation, I should advise you to go into it as hard as possible, for I believe it is easily learnt, and better than Old Notation. I play a flute myself, and I find the Sol-fa to far exceed the Old Notation; and although knowing the Old, I always prefer the Sol-fa.-FIGARO.

[26752.]-Fog and Foghorns.-You will get answers to almost all your questions, and a great deal of other useful information on the subject, in Tyndall's paper on "The Acoustic Transparency of the Atmosphere," Philosophical Magazine, Vol. XLVII., p. 374. I think the last edition of his work on Sound also contains this paper.-J. B., Belfast.

[26753.]-Diabetes.-Le Bon, in his "Physiologie Humaine appliquée à l'Hygiène et à la Médecine," says, on the subject of Diabetes, "It is easily understood that hydropathy, in facilitating the dirculation in the capillaries, and exercise in augmenting the quantity of oxygen absorbed, have a happy influence on Diabetes in favouring the oxidation of the sugar that is formed. Diminution in the saccharine and sugar found in the blood. But in the latter periods feculent aliments likewise reduces the quantity of Griesinger three-fifths of the albuminous matters conof the disease the sugar is formed at the expense of tained in meat can then be converted into sugar. the nitrogenous aliments themselves. According to In suppressing feculents from the diet of diabetic patients the effects of the disease only are attacked, and not its cause. But in medicine the knowledge of the 'cause' is so rare that we are most often resuch therapeutics may be." Mr. Dale, in "Comduced to combat the symptoms, however uncertain pendium of Practical Medicine," gives the following dietary, recommended by Dr. Vavy:-" He may use butcher's meat of all kinds except liver, ham, bacon, or other salted, dried, or cured meats; poultry, game, fish of all kinds, fresh, salted, or cured; animal soups not thickened, beef-tea and broths; the almond, bran, or gluten substitute for ordinary food; eggs dressed in any way, cheese, green lettuce, celery, and radishes butter, cream; greens, spinach, water-cress, mustard and cress, sparingly; jelly flavoured, but not sweetened, blancmange made with cream and not milk, custard made tea, coffee, cocoa from the nibs; dry sherry, claret, without sugar; nuts of any description sparingly; brandy, spirits not sweetened, Burton, bitter ale sparingly. He may not use sugar in any form, bread, wheaten or otherwise, rice, arrowroot, sago, tapioca, vermicelli, potatoes, maccaroni, carrots, parsnips, turnips, peas, French beans, Brussels sprouts, cauliflower, brocoli, asparagus, seakale; pastry and puddings of all kinds; fruits of all kinds, fresh or preserved; milk, except sparingly; sweet ales, mild or old; porter and stout; all sweet wines; port wines, except sparingly."-A. D. H.

[26755.]-How to make a Roller Blind Waterproof.-Take 4 ounces of soap, put it into one gallon of water, and boil until the soap is dissolved; then put it into a tub, add one gallon of cold water, put the article in, let it stop there until thoroughly saturated, take it out but don't wring it, hang it up, and when the water has done running off put into a solution of alum and water. Take two pennyworth of alum, boil in one gallon of water, add same will be best if dried quick in the sun. It will not be amount of cold, soak well, then hang up to dry. It winter. The above will do for clothes without permanent. but I should say it will do a whole spoiling them.-FRANCOIS.

[26760.]Russian Leather. Since my last letter I am able to supply the desired information. an earthen pot with a handful of tripoli betwixt Birch oil is made by distilling 20 pints of birch bark with one of Ledum palustre, crammed in layers into each layer. The mouth of the pot is closed with a perforated oaken plug, and being inverted is luted to the mouth of another pot sunk in the ground. The upper pot being then surrounded by fire, a brown lower jar. An eight-gallon pot, properly filled, yields empyreumatic oil is distilled per descensum into the from 2lb. to 24lb. of oil. In Siberia it is prepared without the Ledum, which imparts a rosy smell. This oil is liquid when fresh, but grows thick in time. It is used for currying the well-known Russian JOSEPH WILLIAM FENNELL. leather, and might profitably be more variously applied. It is infallible against dust and insects.