244 CATTLE. 



beast should be secured, and the hair cut closely from the throat, 

 over the windpipe, and opposite to the fifth or sixth ring:. The skin 

 is then tightened by the finger and thumb, and an incision is made 

 through it, at least three incnes in length. This must be carefully 

 dissected off from the parts beneath, and then a portion of the wind- 

 pipe, half an inch wide, and an inch in length, carefully cut out. 

 The lips of the wound should be kept open by threads passed through 

 the edges and tied over the neck, until the pressure or inflammation 

 above no longer exists, and then they may be brought together and 

 the wound healed. 



It is wonderful what instantaneous and perfect relief this operation 

 affords. The beast that was struggling for breath, and seemed every 

 moment ready to expire, is in a moment himself. 



In cases of permanent obstruction, as tumor in the nostrils, or dis- 

 tortion of the larynx or trachea, the animal will generally be consigned 

 to the butcher ; but instances ma}'- occur in which it is desirable to 

 preserve the beast for the sake of breeding, or for other purposes. 

 Then a tube may be introduced into the opening, two or three inches 

 long, curved at the top, and the external orifice turning downward, 

 with a little ring on each side, by which, through the means of tapes, 

 it may be retained in its situation. A favorite cow or bull might be 

 thus preserved, but extraordinary cases alone would justify such a 

 proceeding. 



THE THYMUS GLAND, OR SWEETBREAD. 



There is an irregular glandular body, of a pale pink color, situated 

 in the very fore part of the thorax, vulgarly called the sweetbread. 

 In the early period of the life of the foetus, it is of no considerable 

 size, and is confined mostly to the chest ; but during the latter 

 months it strangely develops itself. It protrudes from the thorax ; 

 it climbs up on each side of the neck, between the carotids and the 

 trachea, and reaches even to the parotid gland, and becomes a part 

 of that gland. It cannot be separated from the parotid ; and when 

 cut into, a milky fluid exudes from it. 



Very soon after birth, however, a singular change takes place ; it 

 spontaneously separates from the parotid ; it gradually disappears, 

 beginning from above downward ; and in the course of a few months 

 not a vestige of it remains along the whole of the neck. It then 

 more slowly diminishes within the chest ; but at length it disappears 

 there too, and its situation is occupied by the thoracic duct. 



It is evidently connected with the existence of the animal previous 

 to birth, and more particularly with the latter stages of foetal life. 

 It seems to be part of the nutritive system. It pours a bland and 

 milky fluid through the parotid duct into the mouth, and so into the 

 stomach, in order to habituate the stomach by degrees to the digest- 



