SCIENCE-GOSSIP. 



247 



CONDI 1 III' uv I . 



III! I IN CALES, I .R.M.S. 



1 "ii." Microscopic si hw Tin- tendenc) 



is well 



1.1.I h be< 1 1 N nil ful ii ■in. . ni trouble to 



VI 1 Burroughs, Welcome and < ... 



'In • .1 ingei I... mppli in" ci 1 1 mi itains not 



bloid Form, each tabloid, 



or, as tl ill it, " Soloid," being ol known 



strength and 1. quiring onl) to be dissolved in i 



■" alcohol ti 1 1 luce .. solution ..1 equally definite 



coni enlral ion. I'lu- stains .11 presenl sold are h 

 Bisma >n, Fuchsine, Gentian Violet, and 



Methylene Blue. Each "Soloid" contains grain, 



and can l»- obtained From the microscopical opticians 

 in tubes of six "Soloids" for the modesl price of 

 We have had an opportunity ol experi- 

 menting with these stains, and can recommend them 



loth ■in. 1 fourreaders. The instructions given 



with the stains are so cleai and practical that w< can- 

 han repn iduce one or two examples for 

 the i» ni in ol microscopists. A saturated watery 

 ■ of fuchsine, methylene blue, gentian violet, 

 ..1 Bismarck brown is obtained by powdering one 

 " Soloid " stain in ; c.c. (two drachms] ol distilled 



1 mil 1 hen well shaking. Five to ten p 

 dilutions with distilled water ol Lhese saturated 

 solutions arc well adapted for ordinary staining 

 purposes. Thus one drachm of saturated solution 

 mad up to two ounces with distilled water gives 1 in 



17, pei cent, solution. A saturated alcoholic 



solution ol methylene blue, gentian violet, or Bisman I. 

 brown ma) be obtained by heating in the same way 

 one "Soloid" stain with a similar quantit) ol 

 absolute alcohol instead of distilled water. A saturated 

 alcoholic ...Union of fuchsine is obtained by heating 

 two "Soloids" with 3 "5 c.c. (one drachm) ol absolute 

 alcohol. A solution of eosin suitable for general 

 staining is obtained by dissolving one "Soloid" in 

 12 "25 c.c. (tfiree drachms) of 50 per rent, absolute 

 alcohol in distilled water. This gives approxim iti Ij 

 a 0'5 per cent, solution. LoffleYs alkaline methylene 

 blue, aniline gentian violet, etc., can be readilj 



is wanted in the same simple and systi 

 way. 



To Stain i-he Tubercle Bacillus. Transfei 

 a small quantity of sputum, containing, if possible, 

 one or more of the small yellowish masses, toaglass 

 slide : cover this with a second slide and rub the two 

 1 until ihe sputum is thoroughly broken up 

 and mixed. I hraw one side ol a 1 lean covei slip 

 across one ol the slides so as to cause a thin film to 

 to il : allow ii to dry in the air, and fix by 

 ;, with the film upwards, three times through 

 the flame of a spirit lamp or Bunsen I. inner. Now 

 place the cover slip film upwards,, and with an edge 

 projecting, on the end of a strip of metal about liall- 

 an-inch wide and eight to len inches long, and care- 

 fully drop the carbol fuchsine solution upon the film 

 so as to cover it with. mi running over on to the metal. 

 Place the metal in the flame at such a distance from 

 the ever slip that the stain just steams gently : care- 



1 . minutes 1 



,| " h r with I ps- Drain oil th tain on 



to blotting pap 1 ■ h ■ \\ 



iier and place 1 ., i n 25 per 



drochl irii id. Wad, well in methylated 



alcohol until 1 tore red 1 I iui awaj : 



ind, .till holding thi ■ ip with 



the forceps, dropa ratei ,,- blue 



upon the film and allow it to slain for thit 



1 ' ' - ' 11 the stain, wash rapidly in 



1 

 dry in the warm air ah.ee ti„ 

 jieighl 1l1.1t the hand can be eo ;ih, hi Id thi n 



I balsam. Tubercle bacilli will be stained red bj 

 the fuchsine; all other organisms will be ■.loured 



blue. V ver ivenient and useful method for the 



pri Ilium an staining and examination ol an 



lion, is in in. .urn it, when fii . .1. in ,, drop of 



l.iiil. r 's methylene blue and remove all surplus stain 



by gently pressing a piei e ol blotting papi 1 upon the 



11 "■ Mil robes, cell nuclei, etc., lake up the 



dye very readily, and show up well although m 



in the (lye itself, which in such a thin film appears 



almost white by contrast. 



Baker's No. i "D.P.H." Microscope. In a 

 ni the Mai. ni. 1 parasite, we gave a des- 

 cription of th imall travelling microscope which Mr. 

 Chas, linker originally made for Major Ross, and 

 with which the latter carried out his investigations. 

 By the co ol thi ami maker, we are now able 



10 illustrate one of twelve microscopes supplied by 



him to the London School ol tropical Medicine, 

 which instrument has recently been submitted to us 

 for inspection. The illustration explains itself, but 



we may call attention to the fact that in 

 Mr. Baker has adopted the lever form 



at, which, originally so adversely criticised. 

 has imw justified its existence as being one of the 

 mosl delicate, ycl steady and reliable adjustments 

 made. The form of tripod foot is steady and gives 

 more room than usual for the adjustment of the under 

 stage arrangements. The microscope is fitted with 

 the usual focussing and centering substage, swinging 

 tail-rod for mirrors, draw-tube, etc. and with the 

 addition of the excellent mechanical stage shown in 

 the illustration costs /.It. Without this last, but 

 with the Nelson type of horse-shoe stage, fitted with 

 sliding bar, the microscope costs £S 8s. This 

 ment can he strongly recommended both foi 

 manship and design, for all purposes of original 

 research. 



