Note 553 — PHARMACOLOGIA. (continued 5)
Reading edition
Since the last edition of this work, Mr. Dalton has discovered the very curious fact, that lime is more soluble in cold than in hot water, and has given a table of quantities from which he concludes that the quantity held in solution by water at 32° Fah: is nearly double that retained by water at 212°. Mr. Phillips has lately taken up the subject, and confirmed the statement of Mr. Dalton.
thus 10.000 gr. of water, at 212°, dissolve 7.8 of lime
10.000 gr. of water, at 32°, 15.2
Mr. Phillips attempts to account for this apparent anomaly “from the effect which heat sometimes produces of increasing instead of diminishing the attraction of cohesion. In the present case, he continues, the affinities which are brought into play are, the attractions of aggregation of the particles of the lime upon each other, the attraction of the lime to form a hydrate with a small portion of the water, and the mutual affinity existing between that hydrate and the water of solution.” And at the high temperature he thinks that the former affinities may be so heightened as to overpower the latter.