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worthy of experimental verification or refutation, and the required experiments may be easily made. I cannot help suspecting that the officer most likely to command the highest degree of canine respect would be the watchman or door-keeper, or whoever else had the power of turning the dog out, or allowing him to come in. If otherwise, a very interesting field of further observation is opened in the determination of the dog's mode of arriving at his conclusions concerning official status: whether the tone of command impresses him, whether he imitates the bipeds, or how otherwise he is impressed.

Further observations are also demanded in reference to a curious statement made by M. G. Rafin, in a communication to the French Academy of Sciences. He states that a large wood fire having been kindled near an ant hill in the Island of St. Thomas, the ants precipitated themselves into it by thousands, until it was completely extinguished, and he proposes to name this species of ant the Formica ignivora. The first impulse on reading this account of the fire-eating ants is one of incredulity, but further reflection on well-known facts modifies this impression. The fascination of a bright light on insects effects a wonderful amount of suicide. When I lived in the neighbourhood of Twickenham (towards Fulwell), I observed during three successive summers that the bottom glass of the road lamps was darkened by a deposit of very small flies that had flung themselves into the flame and perished; and that the ground around the lamps was strewn with thousands of their bodies. A multitude of similar instances may be named. Possibly the fire exerted a similar fascination upon the ants.

By

A correspondent to this journal (page 262) inquires concerning the food of tortoises. I found the same difficulty as he describes in feeding some that I had, but afterwards was very successful by simply placing them on a garden lawn under an inverted packingcase, in the bottom of which was an opening covered with wire gauze, or left open to supply light. They fed heartily on the clover leaves, and also ate some grass. The patches where they had been were distinctly displayed by their industrious mowing. cutting away about three-quarters of an inch of the edges of opposite sides of the packing case, where it rested on the grass, the tortoises were enabled to shift their prison, and did so in their endeavours to burrow under the raised edges. They thus supplied themselves with fresh pasture during the summer, but died in the winter. Their mode of eating shows that it is scarcely possible for them to feed upon loose readygathered leaves. They do not bite the leaf through, but simply pinch it between their horny jaws, then break it by a jerk of the head, but, for this to be done successfully, the leaf must firmly be fixed by roots or otherwise.

The practice of swallowing their own cast-off skins observed by another correspondent seems to be a

part of the established domestic economy of the newt during their breeding time, when they live in water. Those I kept some years ago never failed to perform this duty, though well supplied with earthworms, their staple food.

The International Conference which decided upon the adoption of an universal prime meridian, and selected that of Greenwich for the purpose, also discussed some questions of clock reform, one being the desirability of counting and naming the 24 hours all round, starting from midnight as 24 o'clock. The advantages of this, especially in railway time-tables, would be very great, and the chief objections I have heard is that which is founded on the mere indolence that shrinks from all innovation. But this is really no innovation, excepting as to the time of fixing the 24 o'clock. I spent a few months in Rome in 1842-3 when the time was reckoned in 24 hours as a matter of course; all public announcements of time were made accordingly, but for the benefit of foreigners the time of opening certain theatres, &c., was further explained by adding the " tempo francese," or "French time" as they called the 12-hour enumeration. The "tempo italiano" was counted from the chiaroscuro, or twilight, a very clumsy device, seeing that the 24 o'clock had to be shifted every month. Some of the public clocks had (and possibly still have) a double set of figures. Referring to an old play-bill of the Teatro Alibert, I find that the performance on the 25th January, 1843, was announced to commence "alle ore due di notte," at two o'clock at night, i.e., two hours after the chiaroscuro. In this play-bill no tempo francese is given.

When will science be decently represented in the organization of the British Government in such a manner that its scientific expenditure shall be wisely controlled and distributed? The pitiful anti-climax of the "Challenger" Expedition brings forth this question most glaringly. Here was lavish expenditure in the sumptuous equipment of a magnificent yacht ; every conceivable luxury was generously provided for the selected few who were paid for taking a charming holiday cruise, the avowed object of which was the obtaining of certain scientific information for the enlightenment of mankind at large, and the British nation in particular. By the aid of some genuine workers at home, the crude materials of the yachtsmen have been arranged and edited to form volumes of reference. These volumes contain all the fruits of the expedition (except the pay and personal recreation supplied to the aforesaid holiday-makers); all that can come to the nation that "paid the piper" is in these volumes. All the cost of finding and arranging materials, of engraving and setting-up the volumes has been incurred, and a few copies actually printed at a total prime cost of many thousands of pounds for getting up each volume. This having been done, the multiplication of copies would cost about ninepence per pound for paper and press-work on the sheets,

and a shilling per volume more for binding decently in cloth. Such being the case, the anti-climax to which I have alluded is simply inconceivable. On application being made for copies to be sent to our public libraries, the Government has declared that it cannot afford these few ninepences per pound and shillings per copy.

Compare this with the proceedings of the Government Printing, Office at Washington, whence are issued the noble records of "The United States Naval Observatory," &c. These are not only distributed freely to the American public libraries, but are sent across to the scientific libraries of Great Britain, and not only to them but to individual members of the scientific societies. I have a very valuable series of these reports, and of the Reports of the " Department of the Interior," and other works issued by the United States Government from their Printing Office at Washington. These are sent over to me through their agent, and carriage-paid to London, upon no other asking than that of replying to an official letter enclosing a list of works from which I am asked to select those I desire to have. Generally speaking they are invaluable as original records of most important and laborious scientific investigation. All Englishmen desiring to be patriotic must be bitterly ashamed of this melancholy contrast.

The present favourable position of the most wonderful and beautiful of all the heavenly bodies, the planet Saturn, with its mysterious ringed appendages, reawakens an old project that I have often longed to carry out, viz., the establishment in a suitable part of London of a popular observatory. I don't mean an establishment with amateur observers pretending to do original astronomical work, and thereby supplementing or superseding the Greenwich business; but simply a good astronomical peep-show, where millions of people who have never looked through a powerful telescope, and otherwise never would do so, might have an opportunity of seeing for themselves some of the magnified glories of the heavens. I believe that it might be made commercially self-supporting if well done, and all pedantry severely excluded. No mathematical work could be done nor need be attempted. Both reflecting and refracting telescopes equatorially mounted with the simplest of efficient clockwork would be required; and one telescope should be provided with spectroscopic appliances. The physical phenomena are all that the popular visitor would desire to see, and the fact of having once seen the most striking of these would leave a life-long impression on all intelligent men, women, and children. A small charge, with proper regulations as to time allowed at each instrument, would cover all expenses, including a modest salary to the showman-I beg his pardon-the director. The sun and moon should be shown first with a low power to display all the disc, then with a high power for particular details.

Apropos to telescopes, Mr. Cowper Ranyard lately read to the Astronomical Society a note on the blurred patches that appear in the splendid photographs of the sun taken by M. Janssen at Meudon. Janssen is himself inclined to attribute them to solar clouds or gaseous matter above the photosphere, but Mr. Ranyard has made some experiments indicating that they have their origin within the telescope itself, and are due to heated currents of air in the tube. He produced exaggerated representations of these in the form of ripples by placing a heated body inside his telescope. The difficulty of maintaining a perfect calm within the tube of a large telescope must be great, and the sensitive film used for these instantaneous photographs cannot fail to display any disturbance affecting either the transparency or refractive power of the air in the telescope. I think the question as between these two explanations might easily be settled by taking several pictures of the sun at short intervals apart. If the light patches or blurs are due to cloud-matter in the sun they should appear at the same place in all the pictures, seeing that the space represented by every square millimetre of such pictures is so enormous that no cloud could travel to a sensible distance on the picture in any short period of time; while, on the other hand, the atmospheric irregularities within the telescope must be visibly shifted during small fractions of a second.

DESCRIPTION OF A CONVENIENT FORM

OF LIVE-CELL FOR OBSERVATION
WITH THE MICROSCOPE, AND OF AN
INEXPENSIVE MICROTOME.

HE main drawbacks of most cells for the obser

objects are that they either

leak, or are very difficult to clean. The underdescribed form, which I have lately contrived and used, obviates these defects, and may therefore be of interest to the readers of SCIENCE-GOSSIP. It is of very simple construction, and can be made up at a trifling cost by the help of any ordinary metal worker.

Take a stout ground-edged glass slip, and have fitted to it two sheaths of thin brass, about 3-inch wide. These should be made to fit closely, but not so tightly as to prevent the glass slip from sliding easily through them. To the middle of one end of each sheath is soldered a small brass arm (shaped as in Fig. 2), carrying a fine screw on one arm, which, when secured in position, projects about 1-inch beyond the end of the sheath.

A piece about 1 inch long, cut off a thin glass slide, and a thick india-rubber ring (those used for Cod's patent soda-water bottles serve excellently) completes our requirements.

To put the parts together, slip the sheaths, one on to each end of the glass slide, with their two little screw arms projecting towards each other. Now cut

a small piece out of the circumference of the indiarubber ring, and place it on the slide between the sheaths, with the opening towards one of the long sides of the slide. Place on top of the ring the short piece of glass, and slide the sheaths towards each other, till the small screws project over its ends. Then, by turning down the screws, the ring is compressed between the two pieces of glass, and a perfectly water-tight cell results. By using rings of different thickness, cells of every convenient depth may be obtained.

When one has finished working with it, the whole

It consists of a block of well-seasoned wood, 5×3×3 inches. At 1 inch from one end of the block a hole is bored of such diameter as may be necessary to admit the cylinder of a pewter syringe of about inch internal diameter. This hole runs vertically from the upper to the lower surface of the block. Across the opposite end of the block is cut a horizontal notch, 1 inch deep and wide. Cut off the nozzle end of the syringe, so as to leave a piece of tube three inches long, and cut the handle off the plunger so as to leave only the piston part. This should be packed as neatly as possible, and have

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thing can be taken to pieces in an instant and cleaned. If a well-polished piece of glass, free from flaws, be chosen for the upper plate, its thickness will not be found to interfere very materially with the performance of any power below-inch.

While on the subject of cheap apparatus, I will describe a form of microtome which can be made by any one, with a slight mechanical turn, for about eighteen-pence. In many essential points it is almost identical with that of Mr. A. B. Chapman, described in your June number, as, however, I constructed and used it more than ten years ago, I must claim to be guiltless of plagiarism.

GLASS 3XI

Fig. 5.-Upper Surface of Microtome. soldered to its upper surface a small Z-shaped piece of tin, so as to give the parapin a firm hold on the piston.

Cement the tube into the hole in the block with shellac or elastic glue, so that

one end projects about the thickness of a glass slide above the upper surface, and cement on to the upper surface of the block, along each side of the projecting portion of the syringe, an ordinary ground-edged glass slide, taking care to choose a pair of equal thickness, and with well-rounded edges. Now procure a fine screw running on an oblong-nut: the nut to have a hole to take the head of a wood-screw at each end, and secure it by means of a couple of screws to the under surface of the block, so that the fine screw works up and down in the centre of the pewter tube. Get also one of the coarse iron screws with brass fittings, such as are used to fasten oldfashioned window sashes, procurable from any ironmonger, and fasten this to the under surface of block, so that the coarse screw may work into the notch already described.

To use the machine, place it with the edge of a lath projecting into the horizontal notch. Then by screwing up the coarse screw, it will be firmly clamped to the table, and projecting beyond it, a position extremity convenient for working.

Now turn down the fine screw, and push the piston, with the finger, down through the tube on to it. The well is then filled with a melted mixture of five parts solid paraffin to one part tallow, and the object to be cut embedded in this. The sections are then taken in the usual way, the two

ground edged slides acting as the guides to the

razor.

With one constructed in this way, I have procured sections finer than I have got with any other nonfreezing machine.

I have one further limit to add. In cementing on the two glass slides, take care that, if not quite horizontal, they may tend to form a V, rather than an A with each other, as should the inner edges be the least higher than the outer, the razor will be very quickly blunted, whereas, on account of the razor edge being, as a rule, somewhat curved, the circumstance of the outer edges being a little high is of no moment. Also do not be tempted to make your well of large diameter; inch is quite as large a section as one is likely to want, and the smaller the diameter of the well, the more even will the sections be. Of course a brass tube and plunger may be made

form sori, seated on scarcely perceptible spots, on the underside of the leaves (only rarely on the upper side); the sori were scattered, or irregularly grouped, occasionally in orbicular clusters, round or oval, averaging 300 μ in diameter, convex and elevated. The epidermis persisted round the sori, forming a somewhat dome-shaped investment, ruptured at the summit, where it was pale in colour, but below darkbrown, owing to the paraphyses showing through. These paraphyses, which formed the most striking feature, were arranged in a single ring, surrounding the sorus, just within the persistent epidermis; they were dark-brown, shining, oblong-cylindrical, enlarged at the apex (club-shaped), inclining inwards towards the centre, from 80-100 μ long or more, and about 12-15 μ thick. (Figs. 6 & 7.)

Within these were the uredo-spores, oval, obovate, oblong, or roundish in shape, surrounded by a very

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thick, colourless, warted membrane (Fig. 8, a); contents very pale yellow, with a few oily drops; 30-50 μ long, and 20-24 μ broad. No other spores than these could be seen in situ ; but, on scraping off a few sori, a small number of meso-spores were observed, which differed in being of a darker brownish colour, and less or not at all warted surface; the transition from the uredo-spores to the meso-spores could be clearly traced. (Fig. 8, b and c.) A persistent search revealed a few teleuto-spores, which were oval, not constricted, smooth, and dark-brown; but so small was the number that I incline to the opinion that these were accidentai intruders, and did not belong to the same species. They might have been blown on to the leaf from some neighbouring plant infested with a Puccinia. (Fig. 8, d.)

The plants on which this fungus was found were two small seedlings, not in flower, growing on rubbish which had been thrown out of the canal in cleaning it;

every leaf was infested. If the description just given is compared with that of P. sonchi, which I will proceed to translate from Winter's "Pilze," p. 189, it will be seen that ours was probably the early stage of the latter, but had not yet reached the time for the production of teleutospores. The chief difference lies in the fact that I found the circle of paraphyses round the pustules of uredo spores.

Puccinia sonchi, Desm.-II. Sori at first covered by the epidermis, which is swollen like a bladder, afterwards surrounded by it like a bowl; roundishpulvinate, scattered or grouped without order, brown. Spores roundish, ovate, elliptic or oblong, with a very thick, colourless, warted membrane, and yellow oil, 23-35 μ long, 16-21 μ thick. III.-Sori more compact than in II., roundish‐pulvinate, on the stem oblong, often confluent, scattered, or arranged in circles, or even grouped without order; black, surrounded by brown paraphyses, which are clavately thickened above. Spores on a pretty long, persistent peduncle, elliptic or oblong, somewhat constricted, rounded below, or tapering into the peduncle, only slightly thickened and rounded or cap-shaped, at the apex ; smooth, clear-brown, 30-60 μ long, 19-30 μ thick. Mesospores numerous, similar, but only one-celled; generally more thickened at the apex, reaching 50 μ in length. W. B. GROVE, B.A.

HOW TO KEEP SMALL MARINE AQUARIA.

IN

N SCIENCE-GOSSIP for April of this year, I described two small glass-jar aquaria, which I had started in the middle of October, 1883, as an experiment, and which, up to that time, had proved most successful for so small a quantity of water. Now, on October 20th, 1884, one jar still remains, with four of its original occupants after a most trying time of it.

For the benefit of those who felt interested in my former paper, I will briefly sketch the history of my miniature aquarium during one of the hottest summers we have had for many a year.

My first death was the small A. dianthus, which seemed to grow gradually less for want of fresh sea-water, and ultimately died. About the end of May I left home, but before going, I changed the water of the two jars (from my reserve quart), and stood the jars in a pan of water, covering them with a piece of woollen material capable of keeping moist by capillary attraction; finally placing the whole in a cool dark place.

Upon my return, I was sorry to find the mussels dead, and the water so offensive that the winkles had crawled out, and the two old A. mesembryanthemum, were much contracted; the young had disappeared.

I thought this was a final collapse, especially as the weather had set in very warm. However, I found

that my reserve sea-water was beautifully clear, so I poured off the tainted water, rinsed out jar number one, which was now to become the receptacle for what was still living, and poured the clear water upon the survivors. In half-an-hour matters were “in statu quo ante." A. mesembryanthemum unfolded their tentacles, and Littorina littorea recommenced their travels, although their shells began to show signs of want of lime.

The bad sea-water, the smell of which was simply unbearable, I strained carefully, and corked up in a bottle, keeping it in the dark, and shaking it up vigorously every day. In about ten days it was as clear and sweet as the other; but as the heat of the weather increased I found the greatest difficulty in keeping my little stock from decomposition. I have, however, so far succeeded, that for more than one year I kept alive four out of nine animals in a pint jar of sea-water, without introducing any fresh sea-water or any algæ.

Now that the year is up, I have put into the jar a good clump of ulva, fresh from the coast, and a piece of chalk. The effect is evidently gratifying to the prisoners, for there is a sudden addition of seven young anemones, which I saw ejected myself.

Considering the great heat, and the fact that I confined my experiment strictly to the materials I commenced with, I think that there is as little trouble in keeping a small marine aquarium as in keeping a fresh-water one, provided, of course, that one or two simple laws are followed, and that the animals selected be hardy species.

Addiscombe, Croydon.

EDWARD LOVETT.

GLASTONBURY AND ITS THORN.

THE

By WILLIAM ROBERTS.

HE Somersetshire town of Glastonbury is one of great antiquity. It was called by the ancient Britons Avalon, from the abundance of apple-trees in the district; and by the Saxons Glastn-a-byrig, from which its present name is immediately derived.

Within a short distance of, and in a south-west direction from, the site of the present town, is situated a place known from time immemorial as "Weary Hill,” and here, it is conjectured, the first society of Christian worshippers established themselves in Britain. St. Patrick, who came over from Ireland in 439, is said to have spent thirty years of his life in the convent then existing at the spot. Previous to this saint's visit, the brethren had lived in miserably furnished huts scattered round about the vicinity of the place of worship; and the primitive form of religion, which, after the death of Lucius, the first Christian king of Britain, had fallen into disuse, was again resuscitated with all its former vigour.

In 530 David, Archbishop of Menevia, with seven.

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