Note 2 — Chapter XL · (continued 2)

The manures termed superphosphate of lime and phosphate of potass, were made by acting upon bone-ash by means of sulphuric acid, and in the case of the potass salt neutralizing the compound thus obtained, by means of pearl-ash. For the superphosphate of lime, the proportions were, 5 parts bone-ash, 3 parts water, and 3 parts sulphuric acid of sp. gr. 1.84; and for the phosphate of potass, 4 parts bone ash, water as needed, 3 parts sulphuric acid of sp. gr. 1.84; and an equivalent amount of pearl-ash. The mixtures, of course, lost weight considerably by the evolution of water and carbonic acid.