WITH THE MICROSCOPE. 95 



transudes through the walls of the vessels, and tinges all the neigh- 

 bouring tissues indiscriminately. The fluid is much improved, and 

 its tendency to transude diminished, by the addition of glycerine 

 and a little alcohol. 



Professor Gerlachwas the first who used a carmine injecting fluid. 

 The beautiful carmine injections now made in Germany are prepared 

 with this fluid, or a slight modification of it. I take the receipt from 

 the excellent work of Dr. Frey (Das Mikroskop, 1863). 



Carmine... ... ... ... 77 grains. 



Water ... ... ... ... 70 grains. 



Liquor ammonias ... ... 8 drops. 



The carmine is to be dissolved in the ammonia and water, and 

 the solution left for some days exposed to the air, and then mixed 

 with pure gelatine, made by dissolving a drachm and a-half of good 

 gelatine in a drachm and three quarters of water. Lastly, a few 

 drops of acetic acid are added to the mixture, which is injected 

 warm. 



181. Acid Carmine Fluid. After trying a great many different 

 combinations, I arrived at the following, which answers the purpose 

 exceedingly well : 



Carmine ... ... ... ... ... 5 grains. 



Glycerine, with eight or ten drops of ) 



. , V i ounce, 



acetic or hydrochloric acid ... J 



Glycerine ... ... ... ... ... i 



Alcohol ... ... ... ... ... 2 drachms. 



Water 6 



Ammonia, a few drops. 



Mix the carmine with a few drops of water and, when well incor- 

 porated, add about five drops of liquor ammonia. To this dark red 

 solution, about half an ounce of the glycerine is to be added, and the 

 whole well shaken in a bottle. Next, very gradually, pour in the 

 acid glycerine, frequently shaking the bottle during admixture. Test 

 the mixture with blue litmus paper, and if not of a very decidedly 

 acid reaction, a few drops more acid may be added to the remainder 

 of the glycerine, and mixed as before. Lastly, mix the alcohol and 

 water very gradually, shaking the bottle thoroughly after adding each 

 successive portion, till the whole is mixed. This fluid, like the 

 Prussian blue, may be kept ready prepared, and injections may be 

 made with it very rapidly. 



