

GALLUS DOMESTICUS. 



one better suited in this respect than the celebrated large 

 Bucks County breed, well known in the Philadelphia market, 

 where capons made from these fowls have been sold weighing 

 twenty-five pounds the pair. As in breeding with a special 

 view to making capons, male chickens alone are required, 

 those eggs should be selected to set under the hens which 

 produce males, namely, such as have the sharpest points. 

 The alteration of a chicken into a capon will, in about a 

 twelvemonth, nearly double the size of the bird. Persons 

 wishing to become expert in the operation of making capons 

 may consult Johnson's Farmers' Encyclopcedia, Article Capon, 

 where such ample and minute instructions are given upon 

 the subject, as, with the aid of original drawings, will enable 

 any one to succeed who possesses common dexterity. 



CHEMICAL AND MEDICAL PROPERTIES AND USES. 



The Egg, which is the only officinal product of the fowl, 

 consists of, I. An exterior covering, called the shell ; II. A 

 white, semi-opaque membrane lining the internal surface of 

 the shell ; III. The white or glaire, a viscid liquid contained 

 Hn very delicate membranes. IV. The yelk, inodorous and of 

 & bland oily taste. 



I. The shell consists, according to Prout, of carbonate of 

 lime 97 ; phosphate of lime and magnesia, 1 ; animal matter, 

 with traces of sulphur and iron, 2. The chalk renders the egg 

 absorbent and antacid ; hence its use to neutralize the acidity 

 of wines. When it is burnt, the carbonic acid is dissipated, 

 the animal cement destroyed, and pure lime, with phosphate 

 of lime, obtained. 



II. An albuminous membrane soluble in alkalis, and from its 

 solution is precipitated by acids. At the larger end of the egg 

 it forms the follicula aeris, the air of which, according to 

 Bischoff, contains 23.475 per cent, of oxygen. 



III. The white or glaire is inodorous and insipid, readily 

 dissolving in water, coagulable by a heat of 165 Fahrenheit, 

 and also by acids and alcohol. When coagulated it becomes 

 sapid, and is no longer soluble, either in cold or hot water. 

 From the experiments of Dr. Bostock, it appears to be com- 

 posed of water 85.0, albumen 1.2, in one hundred parts ; and 

 besides shows traces of uncoagulable matter 2.7, and salts 

 0.3, sulphuretted hydrogen gas, and benzoic acid. 



7 



