220 CATTLE. 



have recourse to bleeding from this vein, in garget, or any inflamma- 

 tory affection of the udder, we should betray our ignorance of 

 anatomy ; and still more so siiould we do it if we regarded this milk 

 vein as having any further connection with the secretion of milk, 

 than as being a kind of measure or standard of the power and de- 

 velopment of the vascular system, with the existence of which the 

 secretion of milk, as well as the secretions generally, is essentially 

 connected. 



THE HEART. 



"We can trace the veins in their course down the neck to the heart, 

 and the arteries working their way upward from the heart, the great 

 source of the circulation of the blood. The lungs, on either side, 

 are inclosed in a separate and perfect bag ; each lung has its distinct 

 pleura or membrane. The heart lies between these two membranes ; 

 and, more perfectly to cut off all injurious connection between the 

 lungs and the heart — all communication of disease — the heart is 

 inclosed in a pleura, or bag, of its own, termed the pericardium. 

 This membrane closely invests the heart ; it supports it in its situa- 

 tion, prevents too great dilatation when it is gorged with blood, and 

 too violent action when it is sometimes unduly stimulated. Notwith- 

 standing the confinement of the heart by the pericardium, it 

 beats violently enough against the ribs under circumstances of unu- 

 sual excitation ; and were it not thus tied down, it would often 

 bruise and injure itself, and cause inflammation in the neighboring 

 parts. 



INFLAMMATION OF THE PERICARDIUM. 



This membrane is occasionally the seat of obscure, unsuspected, 

 and fatal diseases. The cow is a greedy animal ; she swallows al- 

 most everything that comes in her way. She will pick up large 

 pins, needles, and nails. A friend of ours lost a cow from some 

 disease which neither he nor the medical attendant understood. On 

 opening her, a piece of wire, two inches in length, was found stick- 

 ing in the pericardium, and which had produced extensive ulceration 

 and gangrene there. 



We are strongly inclined to believe that these diseases occur 

 oftener than has been suspected ; these pointed substances, which 

 in other animals take very strange but generally comparatively harm- 

 less courses, in order to work their way out of the body, select in 

 the cow this dangerous and fatal course. The proprietors of cattle, 

 and of cows particularly— for the cow chiefly, or almost alone, has 

 this strange propensity — should be careful as to the manner of feed- 

 ing them. 



