52 DISEASES OF CATTLE. 



Plate III — Continued. 



or after having had a little oil or lard rubbed upon it to facilitate its 

 passage. There it is allowed to remain two or three minutes, then with- 

 drawn, and the temperature read as in any ordinary thermometer. The 

 clinical thermometer is made self -registering; that is, the mercury in 

 the stem remains at the height to which it was forced by the heat of 

 the body until it is shaken back into the bulb by taking hold of the 

 upper portion of the instrument and giving it a short, sharp swing. 

 The normal temperature of cattle varies from 100° to 103° F. In 

 young animals it is somewhat higher than in old. The thermometer 

 is a very useful instrument and frequently is the means by which 

 disease is detected before the appearance of any external sign. 



Fig. 2. Simple probang. used to dislodge foreign bodies, like apples, potatoes, 

 eggs, etc., which have become fastened or stuck in the esophagus, or 

 gullet. 



Fig. 3. Grasping or forceps probang. This instrument, also intended to 

 remove obstructions from the gullet, has a spring forceps at one end in 

 the place of the cup-like arrangement at the end of the simple probang. 

 The forceps are closed while the probang is being introduced ; their 

 blades are regulated by a screw in the handle of the instrument. This 

 probang is used to grasp and withdraw an article which may have 

 lodged in the gullet and cannot be forced into the stomach by use of 

 the simple probang. 



Fig. 4. Wooden gag, used when the probang is to be passed. The gag is a 

 piece of wood which fits in the animal's mouth ; a cord passes over the 

 head to hold it in place. The ceutral opening in the wood is intended 

 for the passage of the probang. 



Figs. 5a and 5&. Trocar and cannula ; .5rt shows the trocar covered by the 

 cannula ; 5&, the cannula from which tlie trocar has been withdrawn. 

 This instrument is used when the rumen or first stomach becomes 

 distended with gas. The trocar covered by the cannula is forced into 

 the rumen, the trocar withdrawn, and the cannula allowed to remain 

 until the gas has escaped. 



Fig. 6. Section at right angles through the abdominal wall, showing a 

 hernia or rupture. Taken from D'Aborval, Diet, de Med., de Chir. et 

 de Hyg. : a a. The abdominal muscles cut across ; v, opening in the 

 abdominal wall permitting the intestines i i to pass through and out- 

 ward between the abdominal wall and the skin; p p, peritoneum, or 

 membrane lining the abdominal cavity, carried through the opening 

 by the loop of intestine and forming the sac S, the outer walls of 

 which are marked h f h. 

 Plate IV: 



Fig. 1. The liver is composed of innumerable small lobules, from .^ to ^ 

 inch in diameter. The lobules are held together by a small amount of 

 fibrous tissue in which the bile ducts and larger blood vessels are 

 lodged. Fig. 1 of the diagram illustrates the structure of a lobule; 

 V V, interlobular veins or the veins between the lobules. These are 

 branches of the portal vein, which carries blood from the stomach and 

 intestines to the liver; c c, capillaries, or very fine blood vessels, extend- 

 ing as a very fine network between the groups of liver cells from the 

 Interlobular vein to the center of the lobule and emptying there into 

 the intralobular vein to the center of the lobule ; v c, intralobular vein, 

 or the vein within the lobule. This vessel passes out of the lobule and 



