_——S——=—_ 
ASHES. 
fluoride of calcium, 3°85 of carbonate of lime, 2°05 
of phosphate of magnesia, and 3°45 of soda, with 
avery little chloride of sodium. The ashes of 
the bones of men contain about 4 per cent. less 
of phosphate of lime, and nearly 73 per cent. more 
of carbonate of lime than the bones of oxen. The 
incineration of bones differs widely from the in- 
cineration of vegetables in effecting chemical 
changes during the process of combustion ; for, 
with the exception perhaps of phosphate of mag- 
nesia, all the ingredients in the ashes of bones 
exist in exactly the same condition in the ashes 
as in the bones. Yet bones burnt till quite white, 
and recently heated to redness, absorb 75 times 
their volume of pure ammoniacal gas. Animal 
ashes, under the name of bone ash, are sometimes 
employed as a manure; but they have less fertil- 
izing power than ground unburnt bones. See 
article Bonz-MANnuRE. 
Clay Ashes——Various burnt and calcined pre- 
parations are extensively employed in England 
as top-dressings and manures, under the name of 
clay ashes ; and though more the products of cal- 
cination than proper incineration, they require, 
on account of their popular name, to be here 
fully noticed. Many, perhaps most, of these pre- 
parations, differ from the ashy and calcined pro- 
ducts of paring and burning, only in their raw 
material being taken from ditches, banks, hedge- 
rows and waste grounds, and in their true ashes 
being smaller in quantity, and less saline in con- 
stitution. Whenever the raw material has any 
kind of sward, the clay ashes obtained from it 
are substantially the same thing as the turf ashes 
which we noticed in a former section of this 
article; whenever the raw material is a sandy or 
loamy earth, intermixed with weeds and roots, 
the ‘clay ashes’ obtained from it owe their chief 
value to the portion of vegetable ashes yielded 
by the roots and the weeds; and whenever the 
raw material is chalky earth or true clay, with 
scarcely any vegetable intermixture, the clay 
ashes are sheer calcinations, and owe their fer- 
tilizing power partly to mere mechanical action 
upon the soil, and partly to the mineral alkalinity 
of their calcareous or aluminous nature. The 
practice of preparing these clay ashes as manures 
has been long and extensively prevalent in Suffolk, 
in Yorkshire, and in other districts; it is highly 
recomimended by several eminent practical agri- 
culturists, who have inquired into its merits ; and 
yet it does not seem to have been very scientifi- 
cally examined, nor is it practically reported 
upon with a sufficient precision of terms to af- 
ford proper. guidance for its adoption in dis- 
tricts where it has been hitherto unknown. The 
Suffolk method of this practice, though differing 
in some unimportant particulars from that of 
other counties, may be regarded as a model. 
“This method is to dig old borders, surfaces of 
banks, &c.; turn it over, and, when dry, cart it 
to a heap and burn; formerly much wood was 
used, but haulm, straw, dry weeds, and a few 
ASHLAR- WORK. 267 
bushes, whins, or anything of that kind may be 
employed; then build a circular wall of turfs 
around it, cover the heap slightly with turfs and 
earth, and set fire to it in several places ; feeding 
with the most inflammable materials at first, 
afterwards clay or any earth will burn; when all 
the earth is on the heap, the walls may be pulled 
down and thrown on, raising it by degrees as the 
fire ascends, in the shape of a cone, till all is con- 
sumed.” he ashy and calcined product costs 
about 16 pence per load, and is distributed over 
land in the proportion of 50 loads per acre. 
Volcanic Ashes—Some ashes which fell from 
Vesuvius at Naples in 1822, were of a greyish 
colour, and without taste, and were found, on 
analysis, to consist of alumina, oxide of iron, 
muriate of ammonia, gypsum, potash, copper, 
manganese, charcoal, and carbonate of lime. 
Some other ashes ejected from Vesuvius in the 
same year were in fine powder and grey in colour; 
when brought to a red heat in a close vessel, they 
yielded sulphur, but, when brought to a red heat 
in exposure to the oxygen of the atmosphere, they 
threw off the sulphur in the form of sulphurous 
acid ; and, upon analysis, they were found to con- 
sist of 28°1 per cent. of silica, 18° of gypsum, 
20°88 of sulphuret of iron, 8° of alumina, 26 of 
carbonate of lime, 1: of charcoal, and 21°42 of | 
alumina and sulphate of copper, with traces of 
sulphur, a muriate, and moisture. A glance at | 
the constitution of these ashes explains the pe- 
culiar appearance of vegetation around the base 
and upon the acclivities of both active and ex- 
tinct voleanoes.—Dr. Dana’s Prize Essay on Man- 
ures. —Boussingault’s Rural Economy.—Davy’s | 
Agricultural Chemistry. — Liebig’s Chemistry of | 
Agriculture —Johnston’s Lectures on A gricultural 
Chemistry.— Johnson on Fertilizers—Annales De | 
Chimie et De Physique.—Booth and Boye’s Cyclo- | 
pedia.—Keith’s Lexicon —Paper by Dr. Madden in | 
Quar. Journal of Agriculture—The Bath Papers.— 
Malcolm’s Compendium of Modern Husbandry.— | 
Essay by Mr. Mitchell in Transactions of the High- 
land Socrety— Treatise on Flemish Huslandry in 
Lib. of Useful Knowledge.—Museum Rusticum.— 
The Society of Gentlemen's Complete Farmer. — 
Bradley's Husbandry.—Miller’s Dictionary. 
ASHLAR-WORK. Walls faced with squared | 
stones, and backed with rubble or brick, are called 
ashlar work, and the stones themselves are called 
ashlars. The average size of each ashlar is from 
24 to 36 inches in length horizontally, 8 to 12 
inches in breadth or depth, and 10 to 16 inches 
in height. The best figure for the stones of an 
ashlar-facing is that of a truncated wedge, that 
is, thinner at one end than the other in the thick- 
ness of the wall, so that those in one course may 
form in their back parts indentations like the 
teeth of a saw, the next course having its inden- 
tations varied from that below it; the whole is 
therefore toothed or united with the rubble back- 
ing, much more effectually than if the backs of 
the ashlars were parallel with the face. Bond 
