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SOME OF THE PROPERTIES OF WATER' 



By Adolph Lehmann, B. S.A. 



(^Delivered March loi/i, i8g2.) 



In addition to being one of the most wioely distributed substances 

 known to us, Water is one of the most valuable compounds. Without 

 it life from the highest to the lowest forms would be impossible. Owing 

 to its solvent action it is the carrier of plant life in the soil. It enables 

 transformation and translocation of materials in the tissues of all living 

 bodies, enabling them to grow. It plays a part in the electric currents 

 of the atmosphere, ar.d acts as a most powerful equalizer of the climate 

 of our globe. It is one of the principal factors in the formation of 

 soils ; and has at the same time assisted in the production of many of 

 the rock formations. It is a purifier of the atmosphere. In short it 

 may be considered as a balance-wheel of nature. 



Having such useful and varied functions to perform, it would 

 doubtless be interesting to study its properties, even if they were the 

 most simple ; how much more so is this the case when they are, as we 

 find them, very varied and manifold, giving ample room for study and 

 thought. 



Water exists in different forms and locations. In addition to the 

 vast expanse of oceans, lakes and rivers in the Torrid and Temperate 

 Zones, and the plains of ice and snow to the north and south of these, 

 it is present in varying percentages in nearly all organic substances. It 

 can be detected in apparently perfectly dry paper or wood. Hay, 

 straw, and the various grains contain in the neighborhood of lo per 

 cent. We find it also in some perfectly dry crystals, which without 

 this " water of crystallization," as it is called, would fall into powder. 

 It may be interesting to note that while milk (a liquid) contains about 

 87 per cent, of water, cucumbers and melons (solids) are made up of 

 95 per cent, of this compound. The difference is that in the former 

 the solids are largely held in solution, while in the latter they form 

 tissues to enclose the water — as it were a mass of minute sacks, called 

 cells, filled with water. Since it is incompressible it helps to prevent 

 cells from collapsing which, having thin walls, they would otherwise be 

 liable to do. The water in succulent fruits or other parts of the plant 



