Carbonate of lime, with a little oxide of iron 14·58 Carbonate of magnesia 0·44 Sulphate of lime 1·54 Chloride of sodium 1·71 Silicic acid 0·32 Organic matter 0·72 ----- 19·31 Like the preceding water it became turbid when heated to the boiling point, and by continued ebullition for two hours, 12·90 grs. of carbonate of lime, coloured by oxide of iron, were precipitated. Hardness in reference to distilled water as unity = 19. * * * * * C. This water was taken by ourselves from a spring-head near Haslemere, Surrey. The spring issued from the foot of a low sand-hill covered with bushes, and was received into a natural basin about four or five feet in diameter, the bottom of which was lined with pebbles and small gravel. From this basin the water flowed into a large shallow pond. The temperature of the spring at its source was 49° Fahr., that of the air being 56° Fahr. This water was perfectly clear and brilliant, but not sparkling. It had no appreciable taste, but was peculiarly soft and agreeable. It did not contain carbonic acid in a free state, for when mixed with a solution of chloride of calcium and of ammonia not the slightest turbidity was produced. When boiled it did not lose its transparency, nor produce any deposit, until concentrated to about one-sixth of its volume, when glittering scales of hydrated silicic acid separated. An imperial gallon, when evaporated to dryness, left a solid residue, which weighed 5·24 grs. This residue was perfectly white when dried at 300° Fahr.; when heated to low redness, it charred slightly at the edges. The quantity of organic matter was therefore exceedingly small. Hardness in reference to distilled water as unity = 2·4. On analysis, an imperial gallon was found to contain-- Carbonate of lime 2·00 Chloride of sodium 1·46 Sulphate of soda 0·407 Silicic acid 1·143 Organic matter 0·23 ----- 5·24 Traces of an alkaline nitrate were also detected. During the short visit I made with you to Farnham, we examined several other springs near to their sources. In their general characters these waters closely resembled the preceding sample, all of them being remarkably soft, clear, transparent, inodorous, and free from any excess of organic matter, or of oxide of iron. By your desire two samples were subsequently sent to me; one marked ‘Barford,’ the other ‘Boorley.’