84 



ANATOMY AND PHYSIOLOGY OF 



DIRECTIONS FOR INJECTING THE PAROTID 

 GLAND. 



Tliis should be injected before removal, 

 on account of the numerous vessels by 

 which it is attached to the adjacent parts. 

 Before commencing the operation, the sldn 

 over the region of the gland and duct must 

 be raised, in view of searching for the duct; 

 having found it, an opening must be made 

 into it with the point of a lancet, suffi- 

 ciently large to introduce the point of the 

 steel injecting pipe ; when introduced, con- 

 fine the duct upon it by a ligatm-e with a 

 single knot, which shall serve when the 

 pipe is withdrawn to secure the quicksilver 

 in the gland. The gland having been filled, 

 the pipe withdrawn, and the duct secured, 

 we proceed with all possible care to dissect 

 the gland from its situation. Any branches 

 of vessels going off to suiTounding parts 

 must be secured by means of a small 

 curved needle, armed with a single ligature, 

 after which they may be divided with 

 safety. The gland being removed, and all 

 extraneous tissue dissected off, it should be 

 placed in water to extract the blood, etc. 

 This will require about thirty-six hours ; the 

 water, however, must be frequently changed ; 

 the gland can then be spread on a piece of 

 pasteboard and exposed to dry. It makes 

 the most beautiful preparation, when pre- 

 served in a glass vessel containing pure 

 spirits of turpentine. 



BREAKING DOWN THE VALVES. 



Many of the glands, the surface of the liver 

 included, can be injected contrary to the 

 circulation of the lymph. When the quick- 

 silver passes at first freely into the lympha- 

 tics, and suddenly stops, it will be necessary 

 to force it forward by gentle pressure with 

 the edge of a spatula, in the direction in 

 which it seems most likely to run ; by this 

 means the valves are broken down. The 

 valves of the superficial lymphatics of the 

 liver are easily broken down in this way, 

 but the valves in some of the lymphatics 

 are much firmer, consequently not so easily 

 broken down. 



WET PREPARATIONS. 



PREPARATIONS BY DISTENTION. 



Hollow organs may be distended for 

 preservation with antiseptic liquids, air, 

 wool, hair, cotton, plaster, quicksilver, etc. 



Wet preparations by distention^ with 

 spirits of wine, oil of tm-pentine, etc. 



The intention, in distending preparations 

 by spirits, is to give them their natural 

 figure, to exhibit more fully the parts of 

 which they are composed, their vascularity, 

 and occasionally some morbid or preter- 

 natural appearance. 



METHOD OF DISTENDING AND PREPARING 

 THE LUNGS. 



The lungs taken from a sheep or calf 

 make a very good substitute for those of 

 the horse, which are too bulimy for ordinary 

 use. 



The pulmonary arteries and veins should 

 first be filled with red-colored injection ; then 

 immerse the lungs in oil of turpentine, con- 

 tained in a vessel, large enough to admit 

 them without compression; then inject into 

 the trachea such a quantity of the above 

 fluid as shaU dilate them without danger of 

 rupture. Then secure the trachea by liga- 

 ture. In the same manner we proceed with 

 other parts. If a portion only of an organ 

 or a part of some viscera be required, we fu-st 

 secure the lower orifice by ligature ; inject 

 as above, and then apply a ligature to the 

 upper opening. It can then be suspended 

 in spirits of wine or turpentine. 



ANTISEPTIC MENSTRUA FOR PRESERVING 



SPECIMENS. 



Alcohol — Spirits of Wine. — This is one 

 of the principal fluids now in use for the 

 preservation of specimens. It may be used 

 of various strengths, according to the size 

 and thickness of the specimen to be pre- 

 served. 



All those that are thick and bulky should 

 be put into pure rectified spirits ; smaller 

 ones may require only one half the quantity 

 of alcohol with water ; and such as are thin 



