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from his expedition, visited the same district, and writes: "The bed of the Victoria was scarcely ten yards wide (at one point), and perfectly dry, so that it was only after a prolonged search along its course that a small puddled water was found in a hollow. . . During the first two days' journey down the river only a few small pools of water were seen, and these not of a permanent character, while the rich vegetation on the open downs, which had excited the admiration of Sir T. Mitchell, on his discovery of the country in a favourable season, had wholly passed away, leaving little but a bare surface of clay, the deep fissures in its surface giving evidence of long-continued drought." Only at one or two points did Mr. Gregory see anything approaching to a fine river, although in his diary on the 21st of April, 1858, he writes that some good reaches of water were passed. It would seem that the nearer the centre of the continent is reached, the greater the tendency to droughts, although they are considered periodical; but it is clear that if steam navigation is to be carried on in the Australian rivers to any great extent, it will be necessary to employ steamers of very light draught.

THE SMITHFIELD CLUB SHOW.

(Continued from page 25.)

B. Samuelson, of Banbury, exhibited his wellknown turnip cutter, which obtained the first and only prize at Chester; as also a new American reaper, improved by himself. This reaper is selfraking, and, by simple mechanism, leaves the cut grain in sheaves ready for binding, clear of the track of the machine. It is said to work well with one man and two horses, and, at an ordinary walking pace, to cut 5 feet wide and clear 1 to 1 acres per hour. Its low price is a recommen

dation.

Holmes and Sons, of Norwich, exhibited their very recently-constructed portable seed-sheller, which received special award at the Cardiff meeting, and which has an entirely new arrangement of dressing apparatus. The shelling-barrel is placed under the dressing apparatus, and the power applied close to the ground, which causes it to work very steadily; the seed passes from the shelling-barrel into elevators, so as to be delivered into the dressing apparatus, which, being placed above, allows all the hard hulk being delivered into the hopper of the shelling-barrel, to be passed through again, so that no portion has to be lifted a second time to the feeding-hopper. This machine is adapted for 7, 8, or 9-horse engines. Messrs. Holmes also exhibited their very wellknown manure-distributors, which have received eight or ten prizes. The delivery barrels of these machines are made entirely of wrought iron. The scrapers being hung from the top, and being made to clean four deliverers, each one separately has the whole weight of the scraper, thus saving a considerable weight of iron. The machines are also fitted with Messrs. Holmes' "semi-lateral " wheel-stirrers, which are moved without extra gearing or crank action.

Cottam and Co., of Winsley-street, Oxford-street, exhibited, amongst their usual assortment of stable fittings, &c., some cast-iron dairy buckets, enamelled on the inside, and apparently well adapted for the use intended.

George Robinson and Sons, of Barton-onHumber, exhibited their improved and patented clod-crusher roller, the distinguishing feature of which is its non-liability to wear sideways. This is prevented by making the bushes or naves twice the width or length of the outer disc or periphery. By chambering the bushes, twice the bearing surface is given to the spindles, besides receptacles for grease being provided for keeping the spindles lubricated. The discs or rings are so constructed as to split the clods instead of burying them in the ground.

Priest and Woolnough, of Kingston-on-Thames, exhibited a new "pony"-drill for market gardeners and seed-growers, which is sold for ten guineas, and seems well-suited for those farming a small quantity of land; all kinds of grain or seeds being

capable of being drilled by it as by an ordinary
drill. We may also mention Rowley's Patent
Blast Drill, exhibited by this firm, and intended
for protecting the turnip crop from the fly, &c.
This operation is with great difficulty, and very
imperfectly, performed by hand, as the fly usually
shelters and feeds on the under-side of the plant,
where it is almost impossible to apply lime or
other composition. The blast-drill overcomes the
difficulty; as, by it, lime, soot, &c., are thrown by
a powerful blast by means of fans or flyers upon
all parts of the plant, covering both the under
and upper sides of the leaves. The insects are
drawn by the in-current into the fan, and are
destroyed by being mixed with the lime or other
substance. It is more than probable that some
substance may be discovered by which, with the
help of the blast-drill, the diseases of the potatoe
may be effectually arrested; but there are very
many purposes besides those named for which this
implement can be used with great advantage,
such as for light top-dressings to crops. Soot or
guano distributed over turnips, especially when
succeeded by a shower of rain, has been found to
be very beneficial.

A. Lyon, of Windmill-street, Finsbury, ex-
hibited, or rather intended to exhibit, his "noise.
less" sausage cutting and making machine; but,
owing to some unaccountable mode of classifica-
tion adopted by the committee of the show,
sausage and washing machines were ordered to be
put out of the way, as not being strictly of an
agricultural character, although barometers and
butter prints were not excluded, nor was a certain
washing machine, because it happened to be called
a "flax-washer." Indeed, the sausage machines
are intended and made really suitable for prepar-
ing food, both for poultry and pigs; and, there
fore, in every sense of the word, agricultural.
Churns were also exhibited in abundance, as well
as egg-whisks, as indeed everything might con-
sistently be which relates to the preparation of food
for man or beast. By one of Lyon's large machines,
that is, one 16 inches square, 57 lbs. of meal was
cut in 25 minutes at a public trial in Newgate
market. The small machines sold for 30s. cut
and fill 10 lbs. of meat in a quarter of an hour.

according to their breed, fatness, and sex. On this account there are nine different index points on the scale of the guage to every pair of measurements, but when the guage point is decided upon, which every grazier can readily satisfy himself about, the weight of the beast may be very accurately arrived at by the use of the gauge. In the case of ten beasts measured and weighed at the show, and whose weights varied from 57 to 132 stones, the average difference between the estimated and actual weights was only about three per cent., some of them agreeing to within a single pound. This degree of accuracy, it is needless to say, is very rarely, if ever, arrived at by the guessing process. The modes of using the cattle guages are popularly explained in a book of instructions sold with them. We may also notice a very useful instrument for agricul turists, the "garden microscope," said to be "adopted" by the Society of Arts, and which is sold complete for 20s.

Hely and Co. (the Cosmopolitan Glass Company), of 296 Oxford-street, exhibited amongst a very great variety of architectural, horticultural, agricultural, scientific, and domestic glass wares, a new milk test, by which its quality can frequently, if not always, be accurately determined. For the provinces these tests may answer well, but we doubt if London milkmen will be much affected by them, being accustomed with their milk to make up in quantity, that is, in consistency, what it wants in quality. We would, however, recommend the milk test to every good housewife, as were it used bona fide "skim" could never be taken for the genuine article; in other words,

66

new milk from the cow" be confounded with

that from the "cow's tail."

T. Wheeler and Co., of Oxford, exhibited their "Oxonian knuckle" washing machine, which, as its name signifies, attempts the cleansing of linen by an action closely resembling that of the knuckles.

The machine consists of a revolving drum, having upon it half-round ridges running parallel to the axis, and a series of floating discs, which revolve at right angles to the drum. The clothes are carried round the drum and between that and the floating discs or "knuckle rubbers.” Hill and Smith, of Brierly-hill Works, near Wet sheets of paper, and consequently muslin Dudley, exhibited their improved pig-feeding machine without damage. The form of the or other fine textures can be passed through the trough, with shifting divisions for feeding any machines may be varied, the rubbers being somenumber of pigs, and giving them accommodation suitable to their ages, sizes, or dispositions. They times fixed in horizontal frames, the upper one of also exhibited their "continuous which is made to move to and fro by means of fencing, 25 a winch handle. It is not a little curious to see miles of which have been recently fixed up on the London and North-Western Railway. This fenc- very delicate articles passed through these ing is constructed of flat bars nicked out to fit the machines, which, when at work, appear admirably uprights, and then keyed in place, making the calculated to tear to fragments the strongest whole very secure; the depth of the flat bars material. The fact of the discs floating, however, preventing them from being easily bent, offering and thus readily giving way to the slightest as they do their edges in the direction in which pressure, satisfactorily accounts for the real they are most likely to meet with rough usage. delicacy of the work. The principle of the James Tree and Co. (Charlotte-street, Black-machines seems most ingenious, and we think they will be found formidable rivals to the celebrated friars-road), exhibited a great collection of Ewart's cattle gauges-half-a-dozen varieties— ball-washing machines. by means of which, combined with a little judgment, the carcase weight of oxen may he computed with great accuracy from their dimensions, and that of sheep and swine from their weight alive. We notice this instrument not on account of its novelty, but rather from its great utility, and because we have reason to believe a slide rule," which the cattle guage resembles, is looked upon as a mysterious instrument of torture by a very large class of graziers and agriculturists. The most approved method of estimating the weight of cattle appears to be to guess at it, and any aids to the formation of a correct judgment are looked upon with supreme contempt. This may be accounted for partly by the fact that without some judgment being exercised, the cattle gauge would not be very accurate in its deductions. A man must know whether an ox be "half," "moderately," "prime," or "extra" fat, as also whether it be well or ill-bred before he can estimate its weight correctly, even with the aid of the gauge; for it appears that beasts of the same dimensions may vary from 64 to 97 stones,

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F. Edginton, of Northampton, exhibited tents 12 feet square, which are sold for £8, and constructed so as to dispense with the ordinary central pole. This is a great improvement, and renders a small tent on this plan as convenient as a much larger one on the old one.

In noticing Wallis and Haslam's stand we omitted to mention that they were manufacturers of Robey's patented beater for thrashing machines, which consists simply of a bar of iron, having semi-globular indentations made in it on one side, which, of course, produce corresponding projec tions on the other. These projections, as they wear, may be readily set up to the requisite height.

NEW FIRE ENGINE.-On Thursday, January 6, a trial of a new fire engine, constructed on the principle of Mr. Robert's pumps, (illustrated on another page) took place at the anchor and cable works of Messrs. Brown, Lenox and Co., Millwall. The result was highly satisfactory. We shall illustrate the engine shortly.

MOXON, CLAYTON, AND FEARNLEY'S APPARATUS FOR PAYING OUT TELEGRAPH CABLES.

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MOXON, CLAYTON, AND FEARNLEY'S
APPARATUS FOR PAYING-OUT TELE-
GRAPH CABLES.

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MESSRS. Moxon, Clayton, and Fearnley, engineers, of Blue Pits, Lancaster, have devised a most ingenious and effective apparatus for the purpose of preventing undue strain upon telegraph cables during the paying-out of the same. They so arrange the paying-out machine that as soon as an excessive strain is exerted that is, a strain exceeding any given amount decided upon as the maximum strain consistent with safety--the breaks are slacked up and the cable allowed to run out without receiving any additional strain. That their apparatus will effect this object there can be no doubt in the mind of any one who understands its action. This we will now endeavour to make plain :

strain, should any irregularity in the strain of the
cable take place, the regulator acts instantly; the
pulley, C, on the shaft, D, rises and carries with
it the pulley, a', on which the pull of the weights,
G G, comes. Before this takes place, the weights,
G G, draw against the levers, E E', and at the
upper ends of these levers is attached the con-
necting rods, N N, which are connected to the
breaks, so that a given friction is put on the
breaks; but when, as we have said, the friction
becomes too great, the ends, D', of the shaft,
D, travel nearer the fulcra of the levers, E E',
and thus diminish the strain on the breaks.
Instead of the weights, G G, before described,
in a rough sea, the inventors sometimes apply
which would be very liable to prove objectionable
springs, in other cases they retain the weights,
but cause them to work in suitable guides.

GARDNER'S CHAFF-CUTTING MACHINES.

acting in succession from opposite sides of the
material under operation, two or more convex
knives constituting a set act in succession, and
in the same direction to make one cut through
the material fed to the mouth-piece.
a, a, is the
main framing of the machine, carrying at its
upper part the bearings for the shaft, b, of the
fly-wheel, c, to the arms of which the knives, d, d',

are bolted. Two sets of these knives are shown
as applied to the fly-wheel arms, but more or less
may be used, if thought desirable, according
to the diameter of fly-wheel employed. The
knives, d, have a radius that permits of their
passing through and cutting about one-half the
piece, e, to their action, and the knives, d', have a
breadth of the feed presented by the mouth-
radius that enables them, as they revolve, to
complete the cut through the material fed up to
the mouth-piece. The knives may be mounted
on the same or on opposite sides of the fly-wheel
or disc employed to carry them; the feed motion,
whether intermittent or continuous, being ad-

the knives of different radius be fixed on the same or opposite sides of the fly-wheel or disc, Mr. Gardner proposes to set them in different planes; and in order to render them more efficient in their action, he provides a stepped mouth-piece, or a mouth-piece with one part projecting beyond the plane through which the knives of small radius By this means the material, while under the action of the knives of larger radius, is held more firmly up to the cut than it would otherwise be. The invention is patented (No. 1,083, 1858).

move.

The above engraving is a perspective view THE accompanying engraving illustrates the im-justed to suit the action of the knives. Whether of a model of the improved machine. 44proved chaff-cutting machines of Mr. Joseph are the two opposite ends of the cable passing Gardner, of Banbury. The figure is a front round the paying-out drums, B B', several times, elevation. The chief object of this invention is to and thence to the pulley, C, which runs loose on the shaft, D. This shaft carries three other pulleys, a a a", which are keyed upon it; and its enlarged ends, D', rise and fall between the two upright arms of the bent levers, E E'. Connected to, and leading partially around the pulleys, a a", are chains, the other ends of which lead down to a fixed part of the framework; and a third chain, having one end connected similarly to the pulley, a', has its other end attached to one end of the rod, b. The other end of this rod has attached to it a chain, c, the other end of which passes around and is connected to the pulley, c', on the shaft, d. This shaft also carries the pulleys, c and c', which have connected to them chains, passing down to a box, F, carrying as many weights, G G, as may be desired, or found necessary. HH, H' A', are the break-drums, keyed on the same shafts respectively as the paying-out drums, B B'. Land L are the breaks, one end of which is attached to the brackets M and M'. The other ends of the break straps are attached to the connecting-rods, N N, the said rods being connected at their opposite ends to the cross links, O 0, the centre rods, PP, passing through the upper ends of the arms of the levers, E and E', which turn on a pin or stud attached to the frame-end Q. After the weights, GG, have been placed at the end of the chains to give to the cable a certain amount of

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economise the power required to drive the
machines by the use of a peculiar adjustment of
the knives, so that, instead of each cut being com-
pleted by one and the same knife, or by two knives

CONCUSSION FUZES.-In the Times of yesterday, under the head of Naval and Military intelligence, Colonel Wilford, R.A., in his lecture at Woolwich, is made to say:-The concussion fuze of the late Quarter-Master Freeburn, is the best. In the official letter to me, signed Hardinge, lately recorded in your Magazine, he is called Captain Freeburn. The intelligent mechanics who read your Magazine, and who, from the teachings of their mental labour, learn to compose and reason by induction, will be anxious to know the difference between my concussion fuze of 1841, which was in 1843 reported by the Select Committee at Woolwich, to be "simple, safe, and efficacious, being well adapted for horizontal fire with high velocities," and that which Quarter-Master Freebed in Dublin. Will Colonel Wilford at any time burn adopted in 1845, while I was lying on a sick be pleased to favour the public with a drawing of the Freeburn fuse? J. Nearer, Park-villas, 4th January,

AN IMPROVED METHOD OF DRYING
BUILDINGS, &c.

WE bespeak the careful attention of our readers
to the following practical remarks "on some
economic applications of the chloride of calcium,"
by Mr. Desmond G. Fitzgerald, one of the most
observant and enlightened of our rising che-

mists:

It might well be a matter of surprise that the chloride of calcium, so valuable an auxiliary in the laboratory for depriving gases of their hygrometric moisture has not found many important applications of general practical utility. Cheap, easily prepared, free from all deleterious emanations, and lasting indefinitely for the purpose required, its powerful attraction of moisture gives to it a dissiccating property which in many instances may advantageously and economically replace the combustion of fuel. In drying the walls of newly-built houses, for instance, a few pounds of this substance, contained in iron pans, may obviate the expenditure of many hundred weight of coals, the combustion of which acts very inefficiently for the purpose in view. In the usual condition of our atmosphere, the draught of a very large fire can remove from the walls of a newly-plastered room but a comparatively small amount of moisture, the radiated heat being almost ineffectual. But pans of the deliquescent salt, placed in various parts of the room, rapidly abstract the moisture of the air, which, in its dry condition, as rapidly removes the water of the porous plaster. We recently had occasion to point out this fact to an eminent builder, who probably has been the first practically to apply the chloride of calcium to an economie purpose. The iron pans are removed from time to time, as the salt becomes saturated with water, and this is driven off by the application of heat, which is continued until the salt fuses. It may then be broken up with a chisol, and again made use of. Many similar applications of this substance suggest themselves. In wet weather it may serve the laundress as a substitute for expensive fuel by drying linen, &c, suspended in a close room. It is important that the salt should always be contained in a vessel to which heat may readily be applied. An ordinary fire place answers very well the purpose of drying and fusing the dissiccating agent.

The chloride of calcium may be prepared by adding muriatic acid to chalk or limestone in the open air until the effervescence ceases, and then evaporating and fusing the salt by the aid of heat. 100 parts of it may be made to absorb 121 parts of water from the atmosphere. It has been employed for freeing oil of turpentine and alcohol from water.

We will proceed to point out an important application of the chloride of calcium in the manufacture of tobacco. The principal cause of the inferiority of home-made cigars to those of foreign manufacture is the difficulty of removing the water employed in "making up" the leaf after its exportation. Many varieties of tobacco will not "stand" the application of moisture, losing their fragrance, and becoming friable by formentation, whether the moisture be allowed to remain or is partially driven off by heat. In this instance, the rapid abstraction of water, attended with a reduction rather than increase of temperature, is peculiarly valuable. We have, on several occasions, found cigars of English manufacture kept for several weeks in an atmosphere perfectly dried by means of chloride of calcium, to be perfectly equal to the high-priced cigars of foreign make. The plan we adopted was to keep the newly-made cigars in a chest fitted with à tray constructed of metal, and having a perforated cover; the tray being filled with fragments of

fused chloride of calcium..

The judicious employment of this agent may often prove extremely beneficial in a sanitary point of view, A moderately dry atmosphere is the best preservative in cold weather against sudden chills, the effects of which, especially in the case of a weakly constitution, are so dangerous. The result of passing from a sleeping

The effect of improved type of build on the economy of steam transport per ton weight of goods conveyed, is such as shows the inquiry to be of vital importance in connection with the management of steam shipping affairs.

apartment charged with heated vapour-con-aggregate of the foreign trade of Britain, be re-
densing upon the window-panes, and preventing duced not less than 25 per cent. as compared with
a free perspiratory evaporation-into an atmo- the prime cost expenses incurred by steam-vessels
sphere which quickly chills the skin and closes of the average dynamic capability in present use.
the relaxed pores, too often manifests itself in
inflammatory symptoms, especially upon the
lungs. The air of such an apartment may be
freed from unwholesome moisture to any deter-
minate extent by the exposure of a proportionate
surface of the chloride of calcium. We recom-
mend this agent to the attention of the medical
profession; feeling confident that its employment
would, in very many cases, obviate the painful
concomitants of a trying and changeable winter.

DESMOND J. FITZGERALD.

SHIPPING STATISTICS.
(Continued from page 24.)

The public importance of improved type of build in a national point of view (for it is the public and not the shipowners who ultimately bear the brunt of expensive transport service), may be judged of from the statistical fact published by the Board of Trade, that no less than 899 steam-vessels (of which 511 are sea-going ships) were employed on the commercial transport service of Britain in 1857. The ratio in which the transport service of the country is performed by the aid of steam appears to be constantly on the increase, and as it is to be expected that mercantile competition will always cause the cost of freight on the general aggregate of the trade of the country to be proportionally ruled by the prime cost expenses that may be actually incurred in doing the work, it appears manifest that the public economy dependent on the general realization of shipping improvement, is a consideration that involves public interest to the extent of millions sterling

per annum.

To demonstrate the vast importance of this subject an appendix has been compiled from the returns of the Board of Trade, to show the amount of trade between the United Kingdom and foreign countries during the year 1855. This compilation shows that the tons weight of cargo actually carried in the foreign trade of the United Kingdom in the year 1855 amounted toImports.. Exports.....

6,251,259 tons. 8,370,363

ON the important question as to the extent to
which the ordinary smooth-water trial of a
steamer affords a criterion of the general average
performance that may be expected of the vessel at
sea, this committee has not been able to obtain
such an extent of returns of the comparative
smooth-water trials and sea performances of the
same ships as enable them fully to respond to this
part of the inquiry, and they refrain from expres-
sing any speculative opinion, because they have
adopted the principle which they desire to recom
mend to the notice of the British Association,
that shipping improvement is to be discovered by
statistical record and analysis of the constructive
elements of ships that have practically shown
themselves to possess good sea-properties, rather
than by assuming the mere theories of opinionative
speculation, from whatever source such opinions
may emanate; in short, that experience of actual
performances at sea, statistically recorded and
utilised by being made the basis of comparison, is
the most reliable base on which to construct an
inductive system of progressive improvement in
Total......... 14,624,622
naval architecture and marine-engine construction. Nearly 15 millions of tons weight of sea-borne
This committee, however, have much satisfaction in cargo conveyed at probably 25 per cent. extra cost
being enabled to commence this inquiry by record-beyond what would be incurred if ships of the
ing the sea-performance of the before-mentioned high order of dynamic merit exemplified by the
vessel Bremen, on a passage from Bremen Haven Bremen were only and exclusively employed.
to New York and back, during the months of
June and July last, during the whole of which
passages indicator cards were frequently taken,
and the indicated working power of the engines
ascertained. On the out passage the mean dis-
placement was 2,878 tons, the mean indicated
horse-power was 1,078, and the mean speed 10-28
knots per hour, giving a co-efficient by the formula
referred to=201; but on the return passage the
nean displacement was 2,990, the mean indicated
horse-power 1,010, and the mean speed at the rate
of 11-92 knots per hour, giving a co-efficient=318.
Hence, the mean co-efficient of the out and home
passage=276, being about 13 per cent. Below the
co-efficient (319) obtained on the smooth-water
test-trial of the ship. The state of the weather
and the sea was also recorded daily; it appears to
have been adverse on the out passage, but favour-
able on the home passage. The committee are,
therefore, of opinion, that by following up this
course of statistical record of the smooth-water
trial and subsequent sea-performances of ships
respectively, a tabular statement might be com-
piled, showing the probable ratios of the co-
efficients of smooth-water and sea-performance,
corresponding to the various rates of speed for
which steamers may be respectively powered,
whence the smooth-water test-trials of ships may
be made available as approximately indicative of
the sea-service capabilities of ships as respects
their dynamic properties.

Such are the statistical data of the constructive elements and dynamic capabilities of the Bremen, and if all steam-vessels engaged in the mercantile transport service of Britain were equally effective as respects the mutual relations of displacement, speed, and power, that is, capable of producing a co-efficient of dynamic capability=319, by the formula referred to, it is probable that the prime cost expenses of steam-ship transport per ton weight of cargo conveyed on long passages would, on the

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Thus

By aid of the appendix, showing the amount of trade between Great Britain and all foreign countries respectively, parties conversant with shipping affairs will be enabled to estimate approximately the gross amount annually involved in the goods transport service of Britain. public interests require that the statistical records of shipping should embrace such data as will be availably conducive to shipping improvement, by affording the means of approximately estimating the dynamic capabilities of ships, whereby every ship-constructor and ship-owner, and the directors of steam shipping companies, may be enabled to test the dynamic merits and condition of theit ships respectively; a system which would gradually lead to the adoption of such types only as develop a high order of dynamic duty, and would obviate some of the most serious hazards to which private and public interests are now exposed from vessels being employed on commercial and postal services for which they are not fit.

Only let it be publicly known, as exemplified by the Bremen, that steam-ships and their machinery may be so constructed, that on being subjected to a test-trial the cube of the speed in knoty multiplied by the square of the cube root of the displacement, and divided by the indicated horse. power, ought, in the present day, irrespective of future improvement, to produce a quotient or coefficient of dynamic duty equal to the number 319, and that the co-efficient deduced from the rule thus enunciated constitutes (cæleris parile j a criterion of the cost price at which steam-ships perform their work, and we shall then soon fini that this test of dynamic merit, or the numerical co-efficient deduced therefrom, will enter into the calculation of the pecuniary value of steamers to such extent, that ships of a low order of dynamie capability will not be built because the will not sell.

(To be concluded in our next.)

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ROBERTS'S AND DOWNTON'S SHIPS'

PUMPS.

WHEN we undertook-as we did some weeks since -to publish an article of our own upon the relative merits of the Downton pump, which has been so long in use in the navy and elsewhere, and the new pump which Mr. Roberts has lately brought forward, and which has been favourably reported upon to the Admiralty, we undertook a task which is neither easy nor pleasant. A writer knowing very little of either pump might readily satisfy himself in pronouncing an opinion, and another knowing very much about both might do the same; but a writer having a necessarily imperfect knowledge of the two machines, in so far as their actual operation is concerned-which is our case-must find, and must expect to find it difficult to deal with the subject to his entire satisfaction. This will be considered, we know, a damaging admission by some persons, but it is one which we make without hesitation, and which sensible men will construe properly.

Being perfectly well aware that sound practical men attach infinitely more importance to matters of fact than to the mere opinions of the ablest editors in the world, we have, in the first place, been careful to present them with illustrations of the actual constructions of the pumps themselves. The Downton pump, although in very general use for many years, has never before, we believe, had its internal construction publicly described; and Mr. Roberts's pump, although kept less secret than the other, is more perfectly illustrated in the annexed engravings than it has hitherto been. Upon the merits and defects of the respective modes of construction of the two pumps the reader can, therefore, judge for himself. In the

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the rod G3, also at its side, and having one stuffing-box in the centre for the rod G2 to work through. J is the lower bucket, worked from the centre. Ik k3 kkk6 are the valves, and L is the suction-pipe, leading to the hold. L' L' are cap-nuts, covering other suction-pipes, not shown in the section. M is a pipe leading from the suction-plate to the pump. N is the deliverynozzle. cl c2 are fly-nuts, that have to be taken off when the goose-neck is shifted; e e are stuffing-boxes, to make the crank-shaft airtight.

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In the engraving of Mr. Roberts's pump, fig. 1 is a view of the pump, having the suction-plate and part of the front removed to show the valves and water-passages; fig. 2 is a section through the centre, or nearly so; and fig. 3 is a plan of the pump, having the top removed to show the valves, &c. A and A', the cylinders; B is the valve-chamber, having a partition, b, shown in fig. 2. C is the suction-chamber; D, the delivery; E, the plug in the suction-plate; F, the air-chamber; and G, a bolt for holding the airchamber down. ala2 a3 a are passages leading to the cylinders; 61 62 63 64 are the valves; and engravings of the Downton pump, fig. 1 is acc2 c3 c are suction-pipes leading to the hold, section through the centre of the pump; fig. 2, a section through the line of the crank-shaft and suction-plate; fig. 3, a plan of the suction-plate, with three suctions; and fig. 4, a plan of the bucket, showing the manner in which the bucketrods go through. 4 A is the cylinder; B, the suction-plate; C, the goose-neck; D, the footvalve; and E, the crank-shaft. FF2 F3 are cams, and G G G are the rods. H is the upper bucket, worked by the rod G1, at its side, having two stuffing boxes for the rods G and G3 to work through. is the middle bucket, worked by

the sea, &c. These figures are engraved from the pump lately tried at Woolwich.

The manufacturers and supporters of these pumps have conducted a prolonged and bitter controversy on their respective merits, and have devised a most ingenious arithmetical labyrinth, into which we by no means purpose entering. For, in our judgment, the method of conducting comparative trials of pumps now in vogue, and pursued during the late trials at Woolwich, are by no means of a satisfactory character. How is it to be supposed that any reliable result can be ob

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tained by merely clapping a half-dozen or dozen men upon the handles of first one pump and then another, and observing the height to which the water is thrown, or the time occupied in transferring a body of water from one vessel to another? Who is to tell whether the work done by the men upon the one pump is equal to that done upon the other? The mere glance of an officer-to say nothing of bribery, in its many forms-may mar the most careful experiments made by such means. Nor is the mere observation of the number of strokes made per minute sufficient to correct the results by. An average number of strokes may be made with a pump, and yet the volume of water passed through the machine in one minute may be very different from that passed through in another. For, in order to get like results in equal times the velocity of revolution must be uniform throughout the periods. If some pumps are run, for example, at very high speeds, they will deliver less water than when the speed is moderate. The only truly satisfactory way to test pumps comparatively is to put some uniform hydraulic or other like force upon them for equal periods. And if manual trials of pumps are in themselves unsatisfactory, newspaper reports of their results are much more so. We doubt not that the official trials lately

made and reported upon at Woolwich have a
certain decided value; but until their results, as
officially reported, are before us, we are in no
position to discuss the relative per-centages of
gains and losses.

without great credit as the first who has supplied these qualities; on the contrary, he has here a just ground for recompense. But, since the makers of the Downton pump are prepared to supply these qualities without in any way changing Apart from the arithmetical questions in dis- the essential features of the pump, it is not right pute between Mr. Roberts and the gentlemen who to push this matter very far, especially as the write on the opposite side of the subject, there qualities themselves would be of use in exceptional are others in respect to which, we think, some cases only. On the other hand, the theoretical want of fairness has been shown. In the first considerations adduced by "J. S. H," in antaplace, Mr. Roberts brings against the Down-gonism to the Roberts pump, have been pressed ton pump the facts that it is not a portable pump, and that it cannot be itself used as a syphon for running water into the hold to extinguish fires in cargoes. Now, of the Downton pump, as at present fitted in Her Majesty's ships, these statements are quite true, and Mr. Roberts has an undoubted right to adduce them. But, when the alleged deficiencies are urged as important defects, which it is of immense importance to get rid of, and the rival pump is extolled because it is portable and can be used as a syphon, some risk is run of falling into unfairness; because portability and a

capability of syphonic action, are qualities with which the Downton pump can be supplied if desired, and the want of them is incidental, and not necessary, to its use. We do not wish to imply that Mr. Roberts is

too far. As theoretical considerations, and as guides to practice, they are of the utmost importance; but when they are urged as of themselves conclusive evidence against the utility and value of a machine, they are pushed beyond their sphere. It is doubtless desirable that the form and velocity of the water should be preserved as nearly uniform as possible in its passage through any hydraulic machine, whether pump or not; but curious facts of a contrary tendency are observable. For example, if the valves of a pump be examined (through a glass side, or otherwise) while the pump is in action, it will be found that the internal forces are of such a character that the valves seldom open very considerably, however free to open they may be. The fluid, by preference, passes through a small rather than a large

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