CHAPTER XL 



ON MINUTE INJECTIONS. 



MERE dissection, with the most artful management of the 

 scalpel, cannot make a full exhibition of the true structure 

 of animal bodies. The arteries are found, after death, to be 

 emptied of. their contents, and the blood is coagulated in the 

 veins, which appear much collapsed; hence anatomists, in 

 order to examine the circulatory apparatus, are under the 

 necessity of filling these vessels by means of injection, in 

 order to distend them as much as possible, that their ramifica- 

 tions may be clearly seen. More especially is this necessary 

 when it is desired to make an exhibition of the minute 

 capillaries, which are so variously arranged in the different 

 textures and organs of the body. These small vessels, too, 

 require the aid of the microscope to show their size, form, and 

 arrangement. 



The ordinary coarse injection may be made by melting to- 

 gether 16 ounces of bees' -wax, 8 ounces of resin, and 6 fluid- 

 ounces of turpentine varnish, adding such coloring matter as 

 may be desirable, as 3 ounces vermilion, 2 ounces King's 

 yellow, 10 ounces blue verditer, or 5 ounces flake-white. 



This, injected into the blood-vessels by a proper syringe, 

 having its pipe fastened in one of the largest of those vessels, 

 is abundantly sufficient to show the course of the principal 

 arteries and veins. The parts so injected may then be dis- 



