A Practical Manual On Sea Water Distillation
With A Description Of The Necessary Machinery For The Process

STEAM. 41 compartment (S), the steam being admitted at I at, say, 25 lbs. pressure to the square inch, O being the drain or escape for the water as the steam condenses. The following results will be obtained :— 13. The heat imparted by the steam—that is, its sens- ible heat—will be brought into contact with the colder water above, the steam (S) will give up its latent heat, which the water (W) will at once absorb, and carry it away as steam, ready to re-deliver it back to any cold substance that is presented to it, and then reduce itself back again to water. The surface of the partition between S and W would have to be larger than when a gas burner was used ; but, given a surface large enough, the results will be the same. 14. From the foregoing experiment, the following points are to be noted :—Here a certain area or surface was exposed, on one side to the heat of steam, and on the other side to a certain quantity of water. The steam and water surfaces being in contact with the separating plate, the sensible heat (266°) from the pressure steam was im- parted to the water above it, which absorbed such heat, and caused the steam (S) to be at once converted into water. The steam, at the same time, gave out its latent heat, and also occupied a considerably less space as water than it did as steam (the specific volume at that pressure being 645—i.e., the steam occupied C45 times the space it occupies as water). The moment, therefore, that liquefaction took place, the space, thus free, was instantly- occupied by more steam at 25 lbs. pressure, and this process was continually going on until the entire 1 lb. of water (W) was converted into steam. 15. It is, therefore, clear from this, that the heat