222 INJECTIONS. 



or with alcoholic solution of haematoxylin, or with a solution 

 made by adding a trace of dilute sulphuric acid to " liqueur 

 orange No. 3" (a liquid found in commerce, and used for 

 detecting acids) ; the solution takes on a gooseberry red 

 colour. 



The preparation of the injection mass is facilitated by em- 

 ploying acetic acid and ammonia of known strength. For the 

 acetic acid it is sufficient to keep the glacial acid in a well- 

 stoppered bottle. But this will not suffice for the ammonia, 

 which is notably lowered in strength through the mere pour- 

 ing from one bottle into another. Ville has imagined an 

 apparatus which allows of withdrawing a known quantity 

 without permitting any access of air to the stock solution. 

 Description and figures, 1. c. 



With the exception of the processes above described, Ville 

 prepares the injection mass exactly as Ranvier. 



441. Gerlach's Carmine Gelatin Mass (see Arch.f.mik.Anat., 

 1865, p. 148 ; and Kanvier's Traite, p. 113). 



442. Thiersch's Carmine Gelatin Mass (see Ibid). 



443. Carter's Carmine Gelatin Mass (see BEALE, p. 113). 



444. Davies' Carmine Gelatin Mass (see his Prep, and 

 Mounting of Mic. Objects, p. 138). 



445. Hoyer's Carmine Gelatin Mass (Viol. Centralb., 1882, 

 p. 21). Take a concentrated gelatin solution and add to it a 

 corresponding quantity of the neutral carmine (staining 

 solution) (Formula No. 138). Digest in a water-bath until the 

 dark violet-red colour begins to pass into a bright red tint. 

 Then add 5 10 per cent, by volumes of glycerin, and at least 

 2 per cent, by weight of chloral, in a concentrated solution. 

 After passing through flannel it can be kept in an open vessel 

 under a bell-glass. 



446. Eel's Carmine Gelatin Mass (Zeit. f. wiss Zool., xxxviii, 

 1883, p. 492). 



The following method of preparation has the advantage of 

 producing masses that can be kept in the dry state for an in- 

 definite length of time. (Fol finds that the addition of chloral 

 hydrate to wet masses is not an efficient preservative.) 

 320 grammes, and 50 c.c. of saturated solution of mercuric chloride (WANK- 

 LYN). From COOLEY'S Cyclopaedia, s. v. " Nessler's Test." 



