In leaching, ashes lose chiefly the potassium carbonate and phosphate which they contain. Leached and unleached Canada ashes have the following composition:
| Unleached. | Leached. | ||||||
|---|---|---|---|---|---|---|---|
| Insoluble | 13.0 | per | cent. | 13.0 | per | cent. | |
| Moisture | 12.0 | “ | “ | 30.0 | “ | “ | |
| Calcium carbonate and hydroxid | 61.0 | “ | “ | 51.0 | “ | “ | |
| Potassium carbonate | 5.5 | “ | “ | 1.1 | “ | “ | |
| Phosphoric acid | 1.9 | “ | “ | 1.4 | “ | “ | |
| Undetermined | 6.6 | “ | “ | 3.5 | “ | “ | |
In the wood ashes of commerce therefore, it is evident that the proportion of the potash to the lime is relatively low.
The number of parts by weight of the chief ingredients of the ash in ten thousand pounds of woods of different kinds is given in the table below together with the percentage composition of the pure ash, that is the crude ash deprived of carbon and carbon dioxid.
Pounds of the Ingredients Named
in Ten Thousand Pounds of Wood.
| Dogwood. | Sycamore. | Post oak. | Ash. | Red Oak. | Hickory. | |
|---|---|---|---|---|---|---|
| Cornus florida. | Platanus occidentalis. | Q. obtusiloba. | F. Americana. | Q. rubra. | Carya tomentosa. | |
| Potash | 9.02 | 18.06 | 16.85 | 14.94 | 13.95 | 13.80 |
| Phosphoric acid | 5.72 | 9.55 | 6.96 | 1.15 | 5.98 | 5.83 |
| Lime | 6.41 | 24.73 | 35.61 | 7.60 | 27.40 | 18.40 |
| Magnesia | 14.67 | .49 | 5.28 | .10 | 3.05 | 4.86 |
| White oak. | Magnolia. | Georgia pine. | Yellow pine. | Black pine. | Chestnut. | Old field pine. | |
|---|---|---|---|---|---|---|---|
| Q. alba. | M. grandiflora. | P. palustris. | P. mitis. | Picea nigra. | Castanea vesca or sativa. | P. mitis. | |
| Potash | 10.60 | 7.13 | 5.01 | 4.54 | 3.02 | 2.90 | .79 |
| Phosphoric acid | 2.49 | 3.19 | 1.24 | .96 | .92 | 1.09 | .73 |
| Lime | 7.85 | 14.21 | 18.04 | 15.16 | 12.46 | 7.93 | 12.12 |
| Magnesia | .90 | 2.94 | 2.03 | .74 | .10 | .34 | 1.17 |
The Pure Ashes of the Woods
Contain the Following Per Cents
of the Ingredient Named.
| Dogwood. | Sycamore. | Post oak. | Ash. | Red Oak. | Hickory. | |
|---|---|---|---|---|---|---|
| Cornus florida. | Platanus occidentalis. | Q. obtusiloba. | F. Americana. | Q. rubra. | Carya tomentosa. | |
| Potash | 28.04 | 23.17 | 21.92 | 46.04 | 24.66 | 28.60 |
| Phosphoric acid | 8.51 | 12.23 | 9.00 | 3.58 | 10.55 | 11.97 |
| Lime | 38.93 | 31.62 | 46.39 | 23.57 | 48.26 | 37.94 |
| Magnesia | 6.80 | .62 | 6.88 | .60 | 5.38 | 10.04 |
| White oak. | Magnolia. | Georgia pine. | Yellow pine. | Black pine. | Chestnut. | Old field pine. | |
|---|---|---|---|---|---|---|---|
| Q. alba. | M. grandiflora. | P. palustris. | P. mitis. | Picea nigra. | Castanea vesca or sativa. | P. mitis. | |
| Potash | 42.16 | 19.54 | 15.35 | 19.70 | 14.30 | 18.10 | 3.85 |
| Phosphoric acid | 9.48 | 8.75 | 3.82 | 4.18 | 4.33 | 6.76 | 4.11 |
| Lime | 29.85 | 38.94 | 55.24 | 65.53 | 58.98 | 49.18 | 67.73 |
| Magnesia | 3.43 | 8.05 | 6.25 | 3.20 | .50 | 2.11 | 6.54 |