86 
EXTRACTS—NATURAL H1STORY. 
/ 
RURAL AFFAIRS. 
0 
Experiments for ascertaining what sort of Wood will remain 
longest without Rotting. —M. Hartwig found that stakes of firs, oaks, and 
Robinia Pseud-Acacia, were, after being five years in the ground, not the least 
altered; while, after two years, almost all others, as Tilia (Lime wood) Betula 
alba , (White birch), Carpinus (Hornbeam) Acer (Maple) &c. were more or less 
rotten. Salix, Juglans , Fagns , Castanea, and Platanus, lasted four years. He 
also observed, that those stakes which had their bark left on, or were, as usual, 
oiled or tarred, did not keep any longer than those without either bark or prepa¬ 
ration ; but that those which were burned a little way above and below the 
ground stood well, particularly when tarred. This being the cheapest method, 
it will be more in use than the following, which, however, is the best way for pre¬ 
serving wood. It must first be painted with oil colour, and, after it is dry, a 
sheet of iron, about sixteen inches long, must be put round it, so as to be as 
much in the ground as above it, and then the whole should be painted again. 
Stakes or posts in this manner, will remain perfectly sound for a long time.— 
Pruss. Gard. Soc. 
Preparation of Chlorate of Potash. —M. Liebig proposes the following 
process, for obtaining chlorate of potash. Heat chloride of lime till it ceases to 
destroy vegetable colours. In this case a mixture of chloride of calcium and 
chlorate of potash is obtained. This is to be dissolved in hot water, and to the 
solution, concentrated by evaporation, chloride of potassium is to be added,and 
then suffered to cool. After cooling, a quantity of crystals of chlorate of potash 
is obtained, which are to be re-dissolved and crystallized again to purify them. 
M. Liebig considers, that this will be a cheap process for obtaining chlorate of 
potash. From twelve ounces of chloride of lime, of so bad a quality, that it left 
65 per cent, of insoluble matter, he obtained an ounce of chlorate of potash. 
The only difficulty to overcome in this process is, that the chloride of lime is 
not so easily decomposed by heat as is generally supposed : a solution of it may 
be kept boiling for an hour without losing its bleaching power. The best me¬ 
thod is to form a thin paste with chloride of lime and water, and then to evapo¬ 
rate it to dryness; if it be required to prepare it by passing chloride into cream 
of lime, it is advantageous to keep it very hot. The chlorate of potash, which 
separates from the solution by crystallization, has not the form of scales, which 
it usually possesses, but is prismatic; whether this is occasioned by some admix¬ 
ture, has not been ascertained; but on recrystallizing, it is obtained in the usual 
form. The solution ought to be more than suffered to cool in order to procure 
crystals, for the crystallization is far from being terminated even after complete 
cooling; crystals continue to be deposited for three or four days.— Ann. de Ch. 
ct dc Phgs. 
NATURAL HISTORY. 
Power of the Common Bee to generate a Queen. —In one of the earliest 
epochs of the apiarian science, a considerable degree of importance was attached 
to the formation of artificial swarms; and this plan originated in the well known 
fact of several Queens being bred in the same hive during one season, whilst on 
