Part 2 — APPENDIX TO CHAPTER VI.

NOTE I. (p. 215).

Amount of Potash in Different Minerals.

Felspars—

Percentage of potash.

(a) Orthoclase { 9.11 10.28 11.07 12.12 12.47

{ 13.49 14.35 15.21 16.7

(b)Oligoclase 0.50

(c)Labradorite 0.33

Mica { 5.61 6.20 7.23 8.26 8.95

{ 9.00 10.25 12.40 13.15

Amphibole 0.25 2.96

Pyroxene 0.34 2.48

Leucite 13.60 18.61

Zeolites 0.30 9.35 0.98 4.93

Stassfurt potash salts— Per cent.

(a) Polyhallite, potassium sulphate 28

(b) Karnallite (KCl.MgCl₂6H₂₀), potassium chloride 24 to 27

(c) Sylvin, pure potassium chloride.

(d) Kainit (K₂SO₄MgSO₄MgCl₂6H₂O), potassium sulphate 32

(e) Schoenite (K₂SO₄, MgSO₄, 6H₂O), pure potassium magnesium sulphate.

NOTE II. (p. 217).

The quantity of potash obtainable from various plants in the manufacture of potashes on a large scale is illustrated by the following statements. 1000 lb. of the following vegetative products yield the following quantities of potashes:—

lb.

Old spruce-wood 1/2

Old poplar-wood 3/4

Old oak-wood 1-1/2

Corn-stalks 17-1/2

Bean-stalks 20

Grape-vine 40

(Storer, 'Agricultural Chemistry,' vol. ii. p. 108.)