66 INJECTING MATERIALS. 



color as the surrounding tissues that it is difficult to distin- 

 guish them. Hence it is very desirable to rill them with some 

 colored substance. 



The following starch preparation, recommended by Wilder 

 and Gage in their admirable work, " Anatomical Technology," 

 has been found very satisfactory : - 



STARCH INJECTION MASS. 



Dry starch ("Laundry" is good) . . 100 c. c. 



Water, or a 2$ percent aqueous solution of chloral hydrate 100 c. c. 



Alcohol (95 per cent) 25 c. c. 



Color mixture (as given below) 25 c. c. 



"After thoroughly mixing the mass, it should be filtered 

 through one or two thicknesses of moistened paper cambric. 

 To prevent the starch from settling, the cloth should be tilted 

 from side to side, or the mass may be stirred during the filtra- 

 tion. If the mass is not freshly prepared for every injection, 

 the stock mass should be filtered occasionally, to remove hair 

 or any other object that might clog the cannula. 



" Since almost any animal injected may afford some organ 

 worth preserving, it seems better to employ permanent colors 

 in tingeing the mass. Among these w r hich are available, the 

 following, probably, are preferable : vermilion, red lead ultra- 

 marine, Berlin blue, chrome orange, yellow, or green. 



PREPARATION OF THE COLOR. 



Dry color 100 c. c. 



Glycerin 100 c. c. 



Alcohol (95 per cent) 100 c. c. 



" To avoid lumps, which would clog the cannula or small 

 blood tubes, the color should be thoroughly ground in a mortar. 

 It should be stored in a well-stoppered bottle, and is prepared 

 for use by simply shaking. If permanent preparations are 



