STAINS, ETC. 



solution fixes and stains at the same time, and is a val- 

 le reagent for the study of fresh objects. It is a 

 pure nuclear stain. Acetic-acid Alum-carmin. 

 Boil an excess of carmin in a saturated potash-alum 

 solution , when cool, add io per cent, of giacial acetic 

 acid, and filter after several days For use. add enough 

 of the filtrate to distilled water to give it a deep-rose 

 tint, stain for from 24 to 48 hour.-,, and wash for 2 hours 

 in distilled water. Dehydrate in alcohol. This solution 

 has great penetration, and stains the deeper tissue-layers 



j as admirably as the more superficial ones. Beale's 

 Carmin. Dissolve 0.6 gm. of carmin in 2 c.c. of 

 strong ammonia ; lx>il for a few seconds, and stand aside 

 uncovered for an hour, or until the excess of ammonia 

 has evaporated. Then add 60 c.c. each of glycerin and 

 water and 15 c.c. of alcohol ; filter, stand aside to settle, 

 and decant. Csokor's Alum-cochineal. A nuclear 

 and diffuse stain. Nuclei are stained violet, and other tis- 

 sues different tones of red. It is composed of powdered 

 cochineal I gm., and calcined alum I gm., water 100 

 c.c. carbolic acid 0.5 c.c. Delage's Osmium-car- 

 min has the staining properties of carmin and the 

 fixing properties of osmium, and so stains and fixes 

 tissues at the same time. It is prepared by evaporating 

 on a water-bath a strong ammonium-carmin, until red 

 clouds on its surface indicate that the excess of ammonia 

 has disappeared ; and when cool, adding an equal volume 

 of a I per cent, solution of osmic acid. Filter under a 

 bell-jar. As the reagent soon loses its fixing properties, 

 the acid and carmin should be mixed at the time of 

 using. It is said to rival gold chlorid in bringing out the 

 more minute tissue-elements. De la Rue's Cochineal. 

 Exhaust cochineal in boiling water, precipitate the 

 extract with lead acetate slightly acidulated with acetic 

 acid, being careful not to use an excess of the lead. 

 Wash the precipitate with distilled water until the wash- 

 water ceases to give a precipitate with mercuric chlorid ; 

 then decompose it with hydrogen sulphid, filter, and 

 evaporate the filtrate to a syrupy consistence on a water- 

 bath. Dry, and exhaust the dark purple product with 

 alcohol, which dissolves out the carrninic acid. Frey's 

 Carmin. Dissolve in 30 c.c. of distilled water 0.3 

 gm. of carmin, adding ammonia, drop by drop, until 

 the solution is complete. Then add 30 c.c. of glycerin 

 and 4 c.c. of alcohol ; shake, and keep in a stoppered 

 bottle. Grenadier's Alcoholic Borax-carmin. Dis- 

 e 4 gm. of borax in 100 c.c. of distilled water; add 

 3 gro of carmin. warm, and dilute with loo c.c. of 

 70 per cent, alcohol. Filter before using, and transfer 

 the tissue from the stain directly into alcohol acidulated 

 with from 4 to 6 drops of hydrochloric acid, in which it 

 should remain until it acquires a bright, transparent ap- 

 pearance. This solution is used for staining in bulk, 

 and gives a splendid color. Grenadier's Alum-car- 

 min. Dissolve 5 gms. of ammonium-alum in 100 c.c. 

 ot distilled water, adding 1 gm. of carmin, cooling, 

 filtering, and bringing up to 100 c.c. by adding water. 

 This solution is not suitable for calcareous structures, 

 but is otherwise an admirable reagent. Grenadier's 

 Borax-carmin. Heat to boiling carmin 0.5 gm., borax 

 2 gm. in 100 c.c. of distilled water, and while hot add, 

 drop by drop, about 17 c.c. of acetic acid, or until the 

 color turns from purple to red. After 24 hours decant, 

 filter, and add 0.5 c.c. of carbolic acid. Hamann's 

 Acid Carmin. Dissolve 30 gm. of carmin in 200 c.c. 



I of strong ammonia ; add acetic acid until the fluid be- 

 comes neutral, or is only slightly acid. Allow it to 

 stand for from 2 to 5 weeks, and filter. Haug's Alum 

 Borax-carmin. Take 1 gm. each of carmin and 

 borax, 2 gm. of ammonium-alum, pulverize, and add 100 



j c.c. of liquor aluminis acetatis and boil for ^ an hour; 

 decant, and filter after 24 hours. The solution is ready 



! 



1399 STAINING REAGENTS 



for use in I week. Haug's Ammonium Lithium- 

 carmin. A permanent solution, recommended for 

 preparations which stain with difficulty. Pulverize and 

 boil in IOO c.c. of water, carmin I gm. and ammonium 

 chlorid 2 gm. ; after cooling add from 0.3 to 0.5 gm. of 

 lithium carbonate and, drop by drop, from 15 to 20 c.c. 

 of a strong solution of ammonia. This solution stains in 

 from I to 3 minutes, and gives a gorgeous strawberry- 

 red color. Differentiate in acid alcohol, and follow 

 with absolute alcohol. Heidenhain's Neutral Car- 

 min. Dissolve I gm. of carmin in 3 c.c. of ammonia, 

 and add 96 c.c. each of glycerin and water. Heat on 

 a water-bath until the excess of ammonia is driven off, 

 or neutralize with acetic acid. Henneguy's Acetic- 

 acid Alum-carmin. Boil an excess of carmin in a satu- 

 rated solution of potassium-alum, and when cool add 10 

 per cent, of glacial acetic acid, and leave the mixture to 

 settle for several days ; then remove the sediment by 

 filtration, and for use add enough of the solution to dis- 

 tilled water to produce a deep-rose tint. Stain for from 

 24 to 48 hours, and wash for 2 hours in distilled water. 

 Hoyer's Alcoholic Carmin. Heat the carmin in a 

 retort with alcohol, acidulated with sulphuric acid, until 

 dissolved ; filter, and dilute freely with water. As long 

 as a rose-red precipitate forms, add lead acetate to the 

 filtrate. As soon as the precipitate is violet, filter, and 

 add to the filtrate lead acetate as long as the violet pre- 

 cipitate forms ; collect it on a filter, wash, and dry it. 

 Suspend it in a small quantity of strong alcohol, add 

 alcohol strongly acidulated with sulphuric acid until the 

 violet precipitate loses its color and becomes intensely 

 red. Filter. Two drops of the filtrate added to a watch- 

 glass of alcohol make a strong stain. Hoyer's Am- 

 monium-carmin. Dissolve I gm. of carmin in from I 

 to 2 c.c. of strong ammonia and from 6 to 8 c c. of water. 

 Heat in a glass vessel on a sand-bath until the large 

 bubbles become small, and the purplish color turns to 

 bright-red. showing that the free ammonia has evapo- 

 rated. Allow the solution to cool and settle, saving the 

 bright-red deposit for use again, and add chloral to the 

 neutral, Hark fluid, which will keep well. Hoyer's 

 Neutral Carmin. Dilute ammonium-carmin with from 

 4 to 6 times its volume of strong alcohol; collect the 

 scarlet-red precipitate which forms on a filter, wash and 

 dry it. Dissolve this powder in a solution of neutral 

 ammonium picrate. Mayer's Aluminum Carmin- 

 ate. Carrninic acid 1 gm., aluminum chlorid 3 gm., 

 water 200 c.c. , and a few crystals of thymol. Gives a 

 blue-violet color, and is a good substitute for alum-car- 

 min when the use of alum is contra-indicated. Mayer's 

 Cochineal. A nuclear stain, which is red or blue ac- 

 cording to the reaction of the tissues, which should pre- 

 viously have been hardened in 70 per cent, alcohol. 

 Take I gm. of coarsely powdered cochineal and 10 c.c. 

 of 70 per cent, alcohol ; digest for several days and 

 filter. Let the tissues stain, according to size, for 

 from 15 minutes to several days, wash in 70 per 

 cent, alcohol, follow by acid alcohol for a light 

 yellowish-red stain, or ly alkaline water for a deep 

 purple-red. Nnv formula : Pulverize in a mortar. 5 

 gm. of cochineal, mix with 5 gm. of calcium chlorid 

 and 0.5 gm.of aluminum chlorid, add 8 drops of nitric 

 acid (sp. gr. 1. 20) and iooc.c. of 50 percent, alcohol; 

 heat to the boiling-point. Let the mixture stand a 

 number of days, shake it frequently, and finally filter. 

 The objects must be treated with 50 per cent, alcohol 

 before and after staining. Mayer's Carmalum. Take 

 1 gm. of carrninic acid, IO gm. of alum, and 200 c.c. 

 of distilled water, heat the mixture, and filter, adding 

 an antiseptic to keep it clear. The fluid is light-red in 

 color, shading toward violet, and is said to have good 

 penetrating powers, even in osmium preparations, and 



