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HARD WICKE ' S S CIENCE- G O SSI P. 



the thorax and on each of the wings, which quickly 

 spreads over the entire insect, before taking them off 

 the setting board and letting them dry on the boards, 

 which I think is even better than the above, as it 

 almost entirely prevents the fringes of the wings 

 getting matted. — George F. Wheeldon. 



Preserving Butterflies and Moths. — If your 

 correspondent Mr. Pearce will dry his insects in the 

 following manner, the results may be more satisfactory. 

 Pin two setting braces on a piece of cork, and the 

 solutioned insect between them, the braces supporting 

 the wings. The cork may be set before a window, 

 which is opened about two inches, and the door of 

 the room also open, which will cause a good draught. 

 The tails of the insects should point to the open 

 window, in fact come almost under it. The wings of 

 small moths are often broken by the wind in the 

 above method. They are therefore better when dried 

 by the fire. Is it necessary to cover the wings with 

 the solution? I have been told not to do so, and 

 find it answers very well at present. — /. A. S. 



Preserving Butterflies and Moths. — The 

 best way to use the corrosive sublimate solution for 

 the preservation of moths, &c, is, I think, the follow- 

 ing : — Dissolve one part of the sublimate in eight 

 parts of good spirits of wine. Then dip a camel's- 

 hair pencil into the solution, and touch the under side 

 of the insect with it, so as to let the liquor lightly 

 pervade every part of the creature, which it readily 

 does. If a larger portion of the sublimate be used, 

 it will, on drying, cause an unsightly whiteness to 

 appear upon the insect. Before closing the case in 

 which the specimen has been placed, the under side 

 of the board on which the insects are fixed, ought to 

 be slightly warmed by the fire, so that the superfluous 

 moisture may fly off. If this precaution be neglected, 

 the inner surface of the glass will sometimes become 

 obscured by the fumes arising from the mixture. 

 This method of preserving insects was, I think, 

 first used by the great English naturalist, Waterton, 

 and is, if I mistake not, to be found fully described in 

 his book entitled " Wanderings in South America." 

 —J. A T. 



Preserving Larv^ of Lepidoptera. — In reply 

 to query by C. S. as to above, I think the following 

 is the best way of proceeding. Dry the caterpillar 

 with blotting paper— they can be killed by the 

 ordinary cyanide bottle — make a slit in the end of the 

 abdomen, place it between two fresh pieces of 

 blotting paper, and gently squeeze the contents 

 through the aperture, commencing with the head. 

 When the contents are all out, get an ordinary straight 

 glass blow-pipe, but with a piece of watch-spring tied 

 on the end so as to form a spring. Insert the pipe 

 between the skin, let the spring down so as to 

 prevent the larvae slipping off. A grass stem will do 

 very well, but then the caterpillar requires laying on 

 with fine cotton. Next get a spirit lamp with piece 

 of wire gauze over it to keep the caterpillar from 

 singeing. Even an ordinary iron, heated and placed 

 in a stand, so as to keep it face up, does very well. 

 Hold the caterpillar over the gauze, and keep blowing 

 until it is thoroughly dry, which will vary from some 

 seconds to a few minutes, according to the species. 

 Care must be taken not to blow too hard, or the 

 caterpillar will be distended out of its natural shape. 

 With practice, a continuous blowing can be kept up 

 by breathing through the nose. When dry, some 

 mount them on pieces of straw, or artificial leaves, 

 with a pin stuck through the stem, but I prefer moun- 

 ting them on dried leaves of the natural food plant. — 

 George F. Wheeldon. 



Preserving Insects. — Walter A. Pearce should 

 not immerse his insects in the solution of corrosive 

 sublimate and alcohol, but ; merely paint his 

 specimens on the under side of the body (not wings) 

 with the solution. This is quite as effective a 

 preventive against mites, as if the insects were 

 wholly immersed. I had the same difficulty, as to 

 the fringes of the wings and hairs on the thorax, 

 becoming clogged and matted together. Even if 

 covered with French chalk, the effect is the same. 

 T attribute it to the weight of the corrosive, and the 

 density of the spirit. I find also that an insect, after 

 immersion, becomes very limp when dried again, in 

 fact thoroughly relaxed. — W. Finch, jun. 



The Dormouse. — I should be greatly obliged if 

 one of your correspondents would kindly give me 

 some information respecting the dormouse. I wish 

 to know what its most suitable food is ; whether it 

 sleeps during the winter when in confinement, if it 

 should be kept in a warm room, and also if it can be 

 taught any tricks.— Meta. 



The Transit of Venus. — Perhaps the readers of 

 your journal, Science-Gossip, would like to hear 

 what we saw of the Transit of Venus. Telescope 

 used one of Casella's, a terrestrial one, but very good, 

 with unusually large object glass';"dark glass over eye- 

 piece so dark that unless directed to bright edge of 

 cloud close to sun, all was a blank. Terrestrial eye- 

 piece used. In my almanack was set down external 

 contact 1.56 p.m., internal contact 2.16. At 1.55 

 we were ready, but clouds prevented observation. 

 At 2.15 clear view, afterwards no trace of any- 

 thing on sun's disc. All in despair. Well, I said, 

 taking time in London at 2. 16 for first view, we 

 ought to see it at 2.28, so a look at a good clock at 

 hand prepared me. Now, I said, we are three 

 degrees west of Greenwich, and shall see it at 2.28, 

 allowing four minutes for our degree. At 2.29-30, 

 a fair view. When I first saw it, Venus was 

 like this (in a rough sketch), three parts over the 

 line, i.e. the edge of sun ; colour, ash gray. Soon 

 after, j) seen like the small head you see when dis- 

 secting a cauliflower in March' with its stalk. Third 

 view and others a good black disc on sun's face, well 

 defined like a pistol shot through a small illuminated 

 target at twelve paces, a clean punch. We had good 

 views at times up to 3.10 p.m., when clouds prevented 

 any observation. When we saw her last, Venus had 

 not covered over half of her path across the sun's 

 disc. Notes. — The cauliflower appearance fined down 

 to a point. Apparent diameter of sun a very large 

 greengage or orange. I will send, if you like, my 

 rough original, but true sketches of what we saw. 

 Direction of stalk, due east : head, due west. Path 

 of transit much higher than I thought. — A. II. 

 Birkett. 



Extracting Minute Snails.— Can any of your 

 readers inform me how to extract the animal from 

 very minute land shells, and if there is any process 

 that will absorb the animal without injury to the 

 shell. — G. E. Bishop, Watford. 



Scarcity of Acorns. — The following is, I 

 think, the correct way of accounting for the scarcity 

 of acorns mentioned by A. H. Fisher, in the Nov. 

 number of Science-Gossip : — It is not I think, 

 owing to any deficiency of, or defect in, the con- 

 struction of the organs of fructification, but rather to 

 some obstruction, perversion, or vitiation of the 

 natural powers. In the case of the oak, the most 

 probable .cause of sterility seems to be suspended 

 circulation. This is brought about in the spring 



