﻿208 PICTORIAL MISCELLANY. 



you some general idea of it. But to-night we have another theme 

 And now which of you can tell me of what water is composed ? 



George. I have heard that it was composed of a combination of 

 gases, but I do not know the names of them. 



M. F. Water is a combination of eight parts of oxygen and one 

 of hydrogen, by iveight, or of two parts of hydrogen and one of oxy- 

 gen, by measure. By a series of experiments, which have been 

 made by scientific men, it is known that water can be decomposed, 

 that is, the two gases can be separated. If two thin wires, connect- 

 ed with the poles of a galvanic battery, be so placed that one end of 

 each shall enter a glass vessel, a portion of water contained therein 

 will be decomposed, and the gaseous product will be collected in 

 tubes, fixed immediately over the point of each wire. The wire 

 connected with the positive pole of the battery gives out oxygen ; 

 that with the other, or negative pole, hydrogen. I do not suppose 

 that you can understand fully this matter now, yet it will be well to 

 fix it in your memory. 



Flora. Pray, Mr. Forrester, how can air exist in the water ? 

 You told us at the last evening, when we were talking about the 

 atmosphere, that there was air .in the water, and then a short time 

 after, you said air was lighter than water, and that it rose in bubbles 

 to the top of the water. 



M. F. A very proper question. It is now rendered very certain 

 that water is composed of very small particles, nearly, or quite round 

 in form, and that the spaces between are fiLed with air, just like a 

 tea-cup full of fine shot or mustard seed, only infinitely smaller. 

 These particles cannot be seen, they are so small, and the air in 

 water, when it rises in any considerable quantity, displaces them. 

 Liquids, when left to themselves, naturally form into the globular 

 shape. Shot are made by pouring melted lead through a sieve, at 

 the top of some high building. As soon as the drops are left to 

 themselves they acquire the proper shape, and before reaching the 

 ground they cool and become hard. Drops of rain, when falling, 

 are round. Hail-stones are rough when they reach the ground. 

 Now can any one tell me why they are not round like shot, for they 

 are made in the same way, substantially ? 



George. Perhaps it is the wind, for I have noticed that high 

 winds generally accompany hail-storms. 



