March 1, 1868.] 



HARDWICKE'S SCIENCE-GOSSIP. 



07 



MICROSCOPY. 



Elea Cage. — A convenient mode of displaying 

 living insects of various sizes is wanting even to 

 those who possess the usual series of " live boxes " 

 supplied by the best makers. The " animalcule 

 cage" or "capillary tablet," invented many years 

 ago by Varley, is only useful for putting up minute 

 animals living in water, or other objects immersed 

 in fluid. With a lively flea between your finger and 

 thumb you will look in vain for an instrument 

 capable of at once permitting and controlling its 

 action. The best thing you can find for the purpose 

 is perhaps the common live box sold with very 

 cheap microscopes ; but here your flea will be apt 

 partly to hide himself behind the brass collar con- 

 taining the thin glass cover ; that is, if he has not 

 already escaped during your endeavours to put him 

 into the box. 



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Fig. 48. Section of Flea-cage. 



The above diagram is a section of a flea cage 

 intended to supply this want. Its great conve- 

 nience, and the variety of objects to which it may be 

 applied, have been tested by more than a twelve- 

 month's constant use ; very few things, in fact, come 

 amiss to it, from a large bee to the most delicate 

 Nirmus or the smallest Acarus ; all can be im- 

 prisoned and viewed with ease by reflected or trans- 

 mitted light, or with the spot-lens. Both glasses 

 being burnished in, there is no collar to hide any 

 part of the object ; and as the box drops down into 

 the stage, the object is not elevated above its sur- 

 face, which is a great advantage ; as it gives more 

 scope for the use of objectives of the lowest powers. 

 To those who would observe alive the many species 

 of Aphides, flies, gnats, and small spiders frequent- 

 ing our London gardens and houses, this form of 

 inverted live box, or "Elea Cage," is recommended 

 as an inexpensive and useful addition to the micro- 

 scopic apparatus. — H. C. JR., Kensington. 



Wood Sections. — Eew persons who have not 

 studied the structure of wood by the aid of the 

 microscope, are aware of the variety and beauty to 

 be found in the arrangement of the cells, woody 

 fibre, &c, of the various kinds ; and some of your 

 readers, who have little time for study and small 

 means, may have looked with delight on the 



mounted specimens possessed by another, and been 

 prevented from preparing any for themselves by 

 thinking it needful to purchase one of the section 

 cutters recommended in works on the microscope, 

 but which] may easily be .dispensed with in the 

 following manner. Having selected a clean healthy 

 shoot of the wood to be examined, about .' an inch 

 or rather less in diameter and 3 or 4 inches long, 

 cut off the top quite straight across the lower end 

 obliquely, and shave off the bark about A an inch 

 wide for 2 inches of the length; now hold your wood 

 tightly in your left hand, while you carefully cut off 

 a very thin slice from each of the cut surfaces with 

 a very sharp knife or razor ; soaking the wood in 

 water for some days makes it easier to cut than if 

 it is dry. If the sections are very thin, mount them 

 dry ; if rather thicker, so that the light does not 

 easily penetrate them, in balsam. With care a 

 section in each of the three directions may be 

 placed under the cover glass, so that each slide 

 is a complete illustration of one kind of wood. 

 When mounted in balsam, the longitudinal sections 

 are beautiful polariscope objects. — T, Wheatley, 

 Leices. 



Dissecting Needles. — Eor some time past, I 

 have been in the habit of using, as dissecting 

 needles for the microscope, the small steel ticket 

 suspenders made by Messrs. 

 Myers & Son, of Birmingham. 

 Eig. 49, a, shows the shape of 

 the suspender as purchased. I 

 straightened out the hook, as 

 at b, with the aid of a gas jet, 

 then hardened it, and fitted 

 it to a cedar -wood handle. 

 Finding the hardening and tem- 

 pering rather troublesome, I b 

 made further inquiries, when 

 I found that they could be 

 obtained straight, so as to be 

 ready for use at once. The 

 edges may be sharpened so as 

 to answer for cutting, as well 

 as teasing out the tissues. The price is very 

 moderate, the suspenders selling at about twopence 

 per dozen here. I have asked Mr. Charles Collins, 

 the optician, of Great Titchfield-street, to keep a few 

 for inspection, and to supply those who want them. 

 — Charles Adcock, M.R.C.S., Birmingham. 



Soirees.— The most brilliant soiree yet given in 

 connection with Microscopy was that of the Old 

 Change Microscopical Society, which was held on 

 the 17th Eebruary, at the Terminus Hotel, Cannon 

 Street. Nearly 1,200 persons were present. The 

 annual conversazione of the Quekett Microscopical 

 Club will be held at University College, on Eriday, 

 the 13th March. 



Fig. 49. 



