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The power of dissolving substances is a property com- 

 mon to all liquids. And what a curious property it is ! 

 Into this tall glass of water I pour a teaspoonful of salt, 

 and it suddenly disappears as though it were totally anni- 

 hilated. The water does not seem to have been changed 

 in the least. And yet, we need not ask where this salt 

 is, for, when I pour a few drops of water from the tall 

 glass into this hot porcelain dish, pure water is driven off 

 in the form of steam, and we find the salt beautifully 

 crystalized around the edge of the dish. 



If I were to evaporate one gallon of ordinary sea water 

 to dryness, I should obtain about one-quarter of a pound 

 of salt. This does not seem a great amount, but a barrel 

 of ocean water will yield nine pounds of salt. If the 

 ocean were but three feet deep and were then dried up, 

 it would leave a layer of salt at the bottom one inch deep, 

 while if it were three miles deep it would leave, if evap- 

 orated, a layer of salt 280 feet thick. 



It has been estimated that the entire ocean contains 

 three millions of cubic miles of salt. This would make 

 a cube about 140 miles in each of its dimensions. It 

 would just about cover the two states of New Hampshire 

 and Vermont and would be about 150 miles high. 



The question naturally arises, whence comes this great 

 amount of salt? But when we see rivers of water flow- 

 ing through regions of country filled with salt mines, it is 

 easily answered. Some of these salt beds are very large. 

 A single body of salt in Poland is 1200 miles long, 

 twenty miles wide and one-fourth of a mile thick. 



What is salt? The chemist will answer in this way. 

 Pour upon some black oxide of manganese, a substance 

 often used for making oxygen, some strong hydrochloric 

 acid. A dense green gas will be given off, which has a 

 very disagreeable and penetrating odor like chloride of 

 lime, or bleaching powder. Because of its green color, 



