3Q0 BOARD OF AGRICULTURE. 



up, it is required to take an epitomized view of the composition, 

 offices and curiosities of water, which covers three-fourths of the 

 surface of the earth, forms three-fourths of our own bodies, a large 

 part of every tree, shrub, plant, and flower, as well as an indis- 

 pensible portion of the soil we till. This liquid is the result of a 

 subtle union between the well known gases, oxygen and hydro- 

 gen. Experiments prove that hydrogen, while bui'ning in the air, 

 unites with the oxygen of the atmosphere and forms water ; and 

 that water consists of those two gaseous constituents only. 



It is a curious fact that, notwithstanding its power to quench 

 fire, a mixture of its component parts, without chemical combination, 

 constitute a combustible and violently explosive substance ; and 

 that at the freezing point water contains 140° of latent or secret 

 heat. It is more strange than curious that oxygen, so indispensi- 

 ble to animal life, should form eight-ninths, by weight, of a liquid 

 in which few terrestrial animals can live but a few seconds of time. 

 The extent with which it mingles with bodies, apparently the most 

 solid, is very wonderful. The glittering opal, which beauty wears 

 as an ornament, is only flint and water. The glaciers, those 

 mountain mill-stones, a staunch and solid piece of framework as 

 any January could i"reeze together, are but water in a solidified 

 form. In every plaster of Paris statue, which an Italian carries 

 through the streets for sale, there is one pound of water to four 

 pounds of other material. The air we breathe contains five grains 

 of water to each cubic foot of its bulk. The farmer, drawing 

 green wood for fuel, hauls in every cord six barrels of water, and 

 in burning it green, loses heat enough in evaporating the sap to 

 boil about six hundred gallons of water. Even " solid men " are 

 but the representatives each of about five and a half pailfulls of 

 water, through which forty-five pounds of carbon and other ele- 

 ments are diffused. 



Water is a powerful refractor ol light, a good conductor of 

 sound, an impei-fect conductor of electricity, is elastic and com- 

 pressible, although to so small a degree as to be of no consequence 

 in practice. Thirty thousand pounds pressure to the inch will 

 lessen its bulk one-twelfth. In 1650, its compressibility was first 

 fairly shown by the Florentine experiment. Its bulk increases 

 seventeen hundred times by conversion into steam, and about one- 

 fifteenth at the moment of congelation or freezing, when its expan- 

 sive force bursts the strongest vessels. It may be so agitated as 

 to rend into fragments tlie boasted representative of man's inge- 



