THE FARMER AT HOME. 335 



t ie eye, and in others they may be rendered so by the aid of a micro- 



f 3ope. In bodies, whose pores are not thus manifest, the existence of 



1 be intervals between the molecules is proved by various circum- 



t cances. Thus water or mercury being contained in an open vessel 



< f wood over the exhausted receiver of an air-pump will, by the pres- 



s ure of the atmosphere, be forced through the wood, and fall thence 



n a shower ; liquids also are frequently filtered by being made to 



>ass through the pores of paper ; and in the Florentine experiment 



or determining whether or not water is compressible, the fluid was by 



)ressure forced through the pores of the vessel of gold in which it was 



contained. Again, the porosity of bodies is inferred from their elas- 



icity, and the sounds which are heard when the molecules are in a 



;tate of vibration ; also, in transparent bodies and the most dense 



netals are, when rendered sufficiently thin, found to be transparent 



.t is inferred from the fact that the particles of light pass through 



them, or that the vibrations of an sethereal fluid takes place among 



the molecules. Finally, the porosity of bodies is proved from the fact 



that they suffer contraction of volume by being exposed to cold, and 



by mechanical compression, since such contractions can only take place 



in consequence of the particles being forced closer together than they 



were in the usual states of the bodies. 



POULTRY. This term includes all the domesticated birds reared 

 for the table, fowls, turkeys, geese, ducks, and Guinea hens. It might 

 seem a waste of words to attempt proving that poultry should be kept 



