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

COMPOSITION OF WATER. 23 perature at which it may be taken to be at about its maximum density) up to 212°, its boiling point. 13. If, therefore, sea water containing of saline matter has been evaporated so as to reduce it to one-half —i.e., in every 32 lbs. of sea water 16 lbs. of water have been evaporated—there will be left 16 lbs. of brine, with the same quantity of saline matter in it as was in the original 32 lbs. of sea water, thus making the 16 lbs. of brine double the strength of the 32 lbs. of sea water, which is called “ density.” The would equal about 3-12 per cent, of saline matter, and would equal about 6‘25 per cent, of saline matter. If of the 32 lbs. of sea water are boiled away, the remaining | will contain the saline matter originally con- tained in the 32 lbs., and make this | brine three times the strength of the original 32 lbs. of sea water, so that its salinity becomes 14. Sometimes the “ density ” of sea water is said to be meaning that 1 lb. of saline matter in every 33 lbs. of sea water, or 32 lbs. of ordinary water plus 1 lb. of saline matter, making a total of 33 lbs. But (meaning ■jV greater weight than the same volume) is the accepted proportion of salt in sea water, although neither nor quite accords with the accepted percentage of saline matter in sea water—namely, 3'5—for 3'5 per cent, equals between and ?,,, whilst equals 3’125 per cent., and 7;1.! equals 3’03 per cent. However, the matter must rest as it .stands now. Faraday’s analysis of sea water con- taining 32 parts of saline matter per 1,000 parts of sea water, or 3’2 per cent., is certainly nearer than 35 per 1,000, or 3’5 per cent., which is now fixed on as the amount of saline matter in sea water. 15. The prevalent method of denoting the strength or