THE FARMER AT HOME, 53 



congeal, that it may be more easily separated. This, which is called 

 the butter of cacao, is without smell, and, when fresh, has a very 

 mild taste. Its principal use is an ingredient in pomatums. From 

 the nuts, when slightly roasted, an oil is sometimes obtained by pres- 

 sure, which is occasionally used in medicine. 



CACAO TREE. The tree that produces the chocolate-nut, and 

 is a native of South America. In size and shape, it somewhat 

 resembles a young blackheart cherry. The flower is of a saffron 

 color, extremely beautiful, and the pods, which in a green state are 

 much like a cucumber, proceed immediately from all parts of the 

 body and larger branches. As they ripen they change their color, 

 and turn to a fine bluish red, almost purple, with bluish veins. The 

 cacao-tree bears two crops a year, yielding at each from ten to twenty 

 pounds weight, according to the soils and seasons. It is a tree of 

 great delicacy : it is obnoxious to blights, and shrinks at the first 

 appearance of drought. 



CALABASH TREE. The calabash-tree is the production of 

 the West Indies, and the continent of America, about the height and 

 dimensions of an apple-tree, with crooked, horizontal branches, wedged- 

 shaped leaves, pale white flowers on the trunk and branches, and a 

 roundish fruit, from two inches to a foot in diameter. The uses to 

 which the fruit of the calabash-tree is applied are very numerous. 

 Being covered w r ith a greenish yellow skin, which encloses a thin, 

 hard, and almost woody shell, it is employed for various kinds of 

 domestic vessels, such as water-cans, goblets, and cups of almost 

 every description. So hard and closely-grained are these shells, they 

 may even be put several times on the fire as kettles, when they con- 

 tain some fluid, without any injury. When intended for ornamental 

 vessels, they are sometimes highly polished, and have figures engraven 

 on them, which are variously tinged with indigo and other colors. 



CALCINATION. A term given by chemists to that process by 

 which minerals, when exposed to a certain degree of heat, are deprived 

 of their water ; stones converted into lime ; and metals into calx. A 

 metal never becomes calcined, but when in contact with air : the 

 more extensive this contact, the larger is the quantity of metal which 

 becomes calcined : and Lavoisier has proved, that a given quantity 

 of air can only serve for the calcination of a given quantity of metal. 

 The metal thus calcined is termed a metallic calx. 



CALCIUM. This is the name of a metal discovered by Sir H. 

 Davy, and constitutes the basis of lime. It is of a silver color, burns 

 with great brilliance when brought in contact with atmospheric air, 

 and absorbs oxygen so rapidly, that it instantly assumes the form of 

 lime. The term calcareous, as applied to earths containing lime is 

 derived from this word ; and in the form of carbonate of lime, or 

 common limestone, there is perhaps no substance more universally 



