“No. I was manured with well rotted dung from an old melon bed.

“Nó. 2 with the tops of cabbages just come into bloom. " No. 3 with coal ashes.

They vegetated about the same time, but the row manured with the cabbage tops seemed to suffer most from the drought; the season being hot and dry, they made little progress until the end of August, and in Noveniber they were a middling, or rather a bad crop.'

“The row manured with coal ashes had, all along, a more luxuriant appearance than the other two.

The rows twenty yards in length, three feet apart, and fifteen inches from plant to plant in the row.

“I took them up in February, and they weighed as follows :No. 1, 78 lbs.; No. 2, 88 lbs. ; No. 3, 121 lbs. ; which is very much in favour of the coal ashes.'


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may be remarked, that sulphate of lime, which abounds in coal ashes, is found in very sensible quantities in turnips.

In the garden, coal ashes are very useful when spread over the surface, to prevent the depredations of garden mice; they cannot burrow through them; and, in the case of early sown peas, it will be found that the peas covered on the surface of the ground, with coal ashes, say a quarter, or half an inch in thickness, will be three or four days earlier than those to which the ashes have not been applied. This may be attributed to the greater heat absorbed from the sun, by the black coal ashes.


The wood of various trees, &c., has been analyzed by M. Saussure, Jun.; (Chemical Researches on Vegetation); the following was the result :

Parts of Ashes. 1000 parts of the dry wood of a young oak yielded 2 1000 ditto of the bark of oak ...

60 1000 ditto of perfect oak wood

2 1000 ditto of poplar wood

8 1000 ditto of ditto bark

72 1000 ditto of wood of hazel

5 1000 ditto bark of ditto

62 1000 ditto wood of mulberry

7 1000 ditto bark of ditto

89 1000 ditto wood of hornbeam.

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Parts of Ashes.


35 43 15

1000 parts bark of hornbeam..
1000 ditto wood of horse chesnut
1000 ditto straw of wheat
1000 ditto branches of the pine .




100 parts of these ashes were found to consist of the following substances in varying proportions. I have arranged the results in a tabular form, by which my readers will readily ascertain the composition of the ashes procured by the combustion of various woods, barks, &c:



Metallic Loss. 100 parts of ashes Salts. phates.

Silica. Oxides. of young oak dry 26. 28.5 12.25 0.12 1. .58 wood, contain Bark of ditto, ditto.. 7. 4.5 63.25 0.25 1.75 22.75 Perfect oak wood do. 38.6 4.5 32. 2. 2.25 20.65 Poplar wood, ditto.. 16.75 27.

3.3 1.5 24.5 Poplar bark, ditto.. 6. 5.8 60.

4. 1.5 23.2 Wood of the hazel, do. 24.5 35. 8. 0.25 0.12 32.2 Bark ditto, ditto .. 12.5 5.5

54. 0.25 1.75 26. Mulberry wood, do.. 21. 2.25 56. 0.12 0.25 20.38

(Cut in November.) Bark of ditto, ditto. . 7. 8.5 45. 15.25 1.12 23.13 Wood of hornbeam. 22. 23.

0.12 2.25 26.63 Bark ditto

4.5 4.5 59.

1.5 0.12 30.38 Wood of chesnut 9.5 Straw of wheat .... 22.5 6.2 1. 61.5 1. 7.8 Branches of the pine. 15.


The soluble salts of these ashes are chiefly carbonate and muriate of potash. The earthy phosphates are the phosphates of lime and magnesia, (or the principal salt of bones); the earthy carbonates are the carbonates of lime, (chalk); and magnesia silica is the

pure earth of flint ; and the oxides were those of iron and manganese.

The cultivator of the soil will readily see, by the results of these valuable investigations, the reason why wood ashes are so much superior to those from coal as a manure.

The ashes from wood, he will notice, contain a very considerable proportion of the phosphates of lime and magnesia; those from the hazel, containing 35 per cent, and those from the wood of young oak 25 per cent, of which the ashes from coal are entirely destitute.

The phosphate of lime, it will be remembered, is the chief fertilizing constituent of bones, in which valuable manure it is invariably present, in proportions varying from 37 per cent in the bones of the ox, to 35 per cent in the bones of the hare.

Wood ashes also contain a considerable proportion of carbonate of potash, a salt which is more or less present in all vegetable substances, and for which, therefore, it must be highly serviceable as a food. The carbonate of potash, too, promotes the dissolution of dead vegetable substances, and it also, from its attraction of moisture from the air, must promote an increased supply to the soil.

Wood ashes are often very judiciously added to common manure, the quality of which is much improved by the mixture.

The leaves of trees, when burnt, generally produce more ashes, or pot ashes as they are called, (from being formerly produced by burning vegetable substances in large open pots), than the branches, and the stem of the tree the least of all; herbs produce four or five times, and shrubs three or four times as much as either. All vegetables produce more ashes if burnt when green than when they are previously dried. Davy, in his Lectures, p. 113, has given a table of the quantity of pot ashes furnished by the combustion of various common vegetable substances, which we shall here insert, as by it the cultivator will see that there is a very remarkable difference in the quantity produced by equal weights of different trees and plants.

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Parts of

Pot Ashes. 10,000 parts of the poplar produced 7 beech

12 oak

15 elm

39 vine

55 thistle

53 fern

62 cow thistle

196 beans

200 vetches

275 wormwood fumitory



730 * 790

Hence, potash was formerly called “salt of wormwood.”


Peat ashes are made in many parts of England for the use of the farmer, by burning peat in large heaps, after it has been sufficiently dried by the heat of the sun; and for grass lands and turnips they have been found a very valuable manure. It is usually applied as a top dressing.

The composition of peat ashes more nearly resembles that of coal ashes, than those from wood, or vegetables—which is a result hardly to be expected, when we consider that the immense beds of peat, or turf, as it is sometimes called, which are dispersed over Britain, are evidently composed of the remains of vegetable substances. Trunks of trees—leaves—fruits-stringy fibres—the remains of water mosses, &c., and this in some places to a depth of fifteen yards.

Peat ashes were analysed by Sir H. Davy, with much care : he came to the conclusion that they owe most of their fertilizing properties to the presence of gypsum (or sulphate of lime.)

In the Berkshire and Wiltshire peat ashes, he discovered a considerable portion of it. The Newbury peat ashes he found to be composed of from one-fourth to one-third gypsum, and in the peat ashes of Stockbridge, in Hampshire, a still larger proportion of the same substance.

The other constituents of peat ashes are calcareous, aluminous, and siliceous earths, with varying quantities of sulphate of pot ash, a little common salt, and occasionally oxide of iron, especially in the red varieties of peat ashes.

“ These peat ashes, said the illustrous Davy, are used as a top dressing for cultivated grasses, particularly sainfoin, clover, and rye grass. I found that they afforded considerable quantities of gypsum, and probably this substance is intimately combined as a necessary part of their woody fibre; if this be allowed, it is easy to explain the reason why it operates in such small quantities; for the whole of a clover, or sainfoin crop on an acre, according to my estimation, would afford by incineration, only three or four bushels of gypsum. In examining the soil in a field near Newbury, which was taken from below a footpath, near the gate, where gypsum could not have been artificially furnished, I could not detect any of this substance in it, and at the very time I collected the soil, the peat ashes were applied to the clover in the field.”

“ I have mentioned certain peats, the ashes of which afford

gypsum ; but it must not be inferred from this, that all peats agree with them.

“I have examined various peat ashes, from Scotland, Ireland, Wales, and the northern and western parts of England, which contained no quantity that could be useful; and these ashes abounded in siliceous, aluminous earths, and in oxide of iron.

“Lord Charleville found in some Irish peat ashes sulphate of potash. Vitriolic matter is usually found in peats; and if the soil or substratum is calcareous, the ultimate result is the production of gypsum.

"In general, when a recent potash emits a strong smell resembling that of rotten eggs, (sulphuretted hydrogen), when acted upon by vinegar, it will furnish gypsum.”-Agricultural Chemistry, p. 336.


This is hardly the place to enter into the often-argued and yet undecided question, as to the advantages of paring and burning. It is pretty universally agreed, that the practice is highly injurious to sandy soils, beneficial to clay lands, and still more advantageous to those of a peaty description; that is, to soils where there is an excess of inert vegetable remains. The cultivator of the soil will see, by the results of the analysis by Sir H. Davy of the ashes produced by the paring and burning of three different descriptions of soil, the usual products of paring and burning

200 grains of the ashes from paring and burning a chalk soil in Kent, yielded


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80 grains of chalk, 11

gypsum, 9

charcoal, 15

oxide of iron, 3

saline matter, consisting of salpetre of potash,

muriate of magnesia and vegetable alkali, 82

alumina (clay) and silica (flint).


According to the estimate of Mr. Boys, who has published a treatise upon paring and burning, it appears that, on the chalk soils of Kent, about 2660 bushels of ashes are usually produced by paring and burning an acre of ground, and that this

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