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superior to farm-yard manure, in the proportion | only as one ingredient of what is usually desig- 
of five tons of the straw to ten tons of the man- 
ure; but either some egregious mistake has been 
committed in the report, or some enormous over- 
sight was made in the experiments; for the asser- 
tion, or the alleged general principle, that the 
reduction of straw to ashes produces more fertil- 
| izing power than the employment of it in the 
/ usual manner for farm-yard manure, is simply an 
absurdity. 
Soap-Boilers’ Ashes—Soap-boilers’ ashes, in the 
days when kelp and barilla were in universal use, 
formed a manure of considerable importance, but 
| of disputed, ill-understood,and somewhat peculiar 
| mode of action. They consist of the insoluble 
parts of the kelp, barilla, or other coarse alkaline 
matter used in soap-making, mixed with carbon- 
ate of lime, common salt, other saline substances, 
and a considerable proportion of cinders. The 
| insoluble portion of barilla consists principally of 
carbonate of lime, charcoal, silica, and oxide of 
iron; and the insoluble portion of other alkaline 
matters used by soap-boilers, usually consists of 
the same ingredients and some phosphate of lime. 
_ Soap-boilers’ ashes are most useful upon peat- 
moss, cold wet pastures, strong, cold soils, and, in 
_ general, upon whatever kinds of land are most 
benefited by large additions of lime and chalk. 
' About sixty bushels per acre are suitable for 
_ turnips, to be harrowed in with the seed; six 
loads per acre, for wet grass lands; seven loads 
per acre, for wet arable lands; ten loads per acre, 
for poor loamy land; and, in general, nearly as 
large a quantity as common quick-lime, for any 
purpose of general improvement. 
Coal Ashes.—The ashes of coals very consider- 
ably vary in character, according to the chemical 
constitution of the particular coal from which 
they are obtained. The ashes of anthracite, or 
_ almost entirely carbonaceous coal,—the ashes of 
_ flaming and caking coal, or of such as is in a very 
large degree bituminous,—the ashes of cannel or 
shining coal, or such as is employed in the manu- 
| facture of the carburetted hydrogen of the gas 
works,—the ashes of earth-coal, or such as con- 
| tains a large admixture of shaly, stony, and argil- 
| laceous matter,—the ashes of sulphurous coal, or 
| such as is much impregnated with sulphur,—the 
ashes of metalliferous coal, or such as contains a 
very sensible proportion of iron and other metallic 
ores,—the ashes of not a few varieties of coal, in- 
termediate in character among most of the chief 
_ or specific kinds,—all these ashes necessarily differ 
much from one another in constitution, and exert 
_a very different influence upon the soil. Yet 
coal ashes may, in a general view, be character- 
ized as containing a large proportion of earthy 
| and metallic cinders, and a considerable propor- 
| tion of carbonate of lime and sulphate of lime, 
and as exercising upon the soil an influence ac- 
' cordant with the nature of these ingredients. 
Most coal ashes are mixed with the numerous 
refuse matters of towns, and reach the farmer 
nated police manure. Yet though the compost 
to which these belong must be fully noticed in. 
our article on Composts, we may here advert to 
the general fact that, whenever it contains a large 
proportion of coal ashes, it seriously and rapidly 
deteriorates the proper mechanical action of all 
light and porous soils. Hard porous masses of 
matter, or firm irreducible cinders, are formed, 
in the process of combustion out of all the por- 
tions of coal which are strongly impregnated with 
iron and other metallic ores; these cinders pos- 
sess the power of absorbing a considerable quan- 
tity of fluid; and when they are mixed with the 
soil, they become saturated with soluble organic 
matter, the most valuable portion of the food of 
plants, and, in consequence, completely withhold 
it from serving its great purpose of vegetable 
nutrition. This food of plants, indeed, is subject 
to be partially washed out of the cinders by heavy 
rains; but, even in the degree in which it is thus 
returned to the soil, it wants both equal diffusion 
and steady action, and, at the same time, may be 
totally unavailable at the precise periods of the 
plants’ growth when its agency is most required. 
The cinders, besides, are altogether infertile in 
themselves, and quite irreducible to a fertilizing 
condition ; and they consequently act in mixation 
with light soil, both as diluents of its strength 
and destroyers of its slender cohesion. They 
might appear, indeed, to have a serviceable adap- 
tation to strong clayey soils, which require to be 
diluted in their aluminous power, and diminished 
in their cohesive resistance; but unfortunately 
the fertilizing ingredients which usually accom- 
pany the cinders in police manure, are ill suited 
to clay, and best adapted to sands and very light | 
loams. 
Coal ashes, in an unmixed condition, serve as | 
an excellent top-dressing, on clayey lands, for | 
lucern, red clover, sainfoin, and other forage | 
crops; and, when they happen to abound in gyp- 
sum and to be comparatively free from cinders, | 
they are suitable, on most soils, for turnips. They 
are also very serviceable, as a coating or surface- 
covering in the garden, to prevent the depreda- 
tions of mice ; and if spread over a sowing of early 
pease to the thickness of from a quarter of an 
inch to half an inch, they will stimulate the crop 
to an earlier maturity, by several days, than in 
most other modes of culture. They are usually 
employed in gardens either for protecting from 
mice, or for forming walks, or for increasing the 
porosity of clayey soil; and, when employed as a 
manure, they are generally applied in too large 
quantities, and in consequence have been hastily 
pronounced hostile to various herbs and trees, 
which their moderate application would rather 
serve than damage. 
Bone Ashes.—Berzelius, in analyzing the bones. 
of oxen, found that they yielded 66:7 per cent. of 
ashes, and that the constituents of this percent- 
age were 57°35 of phosphate of lime, with a little 
