§20 AGRICULTURAL REPORT. 
per cent. of potassa, and when ignited the alkali becomes entirely mixed 
theteby with strongly-nitrogenized animal charcoal. The result of 
recent experiments tends to show that suant, thus treated, may be used 
with profit in the manufacture of prussiates and cyanides. 
Hard cement.—A cement which becomes excessively hard in time may 
be prepared by mixing two parts of silica, one part of silicate of alumina, 
and nine or ten parts of carbonate of lime, all in powder, and then roast- 
ing in a puddling furnace. The remaining mass is then to be ground 
and again roasted with two or three parts of carbonate of baryta. In 
practice, very pure sand will answer for the silica, and challx for the 
carbonate of lime, the remaining ingredient being supplied by mineral 
witherite or natural carbonate of baryta. 
Petroleum in dry-rot.— According to Herbst, petroleum may be applied 
with good advantage in the extirpation of the dry-rot, it being only 
necessary to paint with the petroleum the surface of wood thus affected. 
A solution of carbolic acid, however, answers the same purpose and 
involves much less danger from fire. 
Destruction of grain by tnsects.—Some idea of the injury caused by 
insects to agricultural products may be formed from the statement that, 
in one instance, from seventy-four tons of Spanish wheat stored in a 
granary, ten hundred-weight of beetles were screened out, and in another 
thirty-five hundred-weight were removed from one hundred and forty- 
five tons of American corn. The offender in both cases was a weevil, 
known as Colandra orise. 
Calomel a poison for mice.—A preparation of one part calomel, five 
parts of wheat fiour, one part of sugar, and one-tenth of a part of 
ultramarine, mixed together in fine powder and placed in a dish, is 
said to be a most efficient poison for mice. 
Glyconin.—A mixture of five parts of glycerine and four parts of the yelk 
of egg, under the name of glyconin, has been used to some advantage 
for the healing of wounds, the mixture forming a varnish over the skin 
impenetrable to air and moisture. 
Curing dampness in walls.—A Russian preparation for curing moisture 
in the walls of houses consists in the use of a mixture made by adding 
two pounds of white resin to a boiling solution of three and three-fourths 
pounds of green vitriol in one hundred pounds of water. To this are 
to be added ten pounds of sifted red ocher, or other color, eight pounds 
of rye meal, and six and a half pounds of linseed oil, and the whole stirred 
together until it forms a completely homogeneous mass. Two coats of 
this mixture are to be applied successively, while hot, but only in dry. 
warm weather. 
Preparation of wooden labels for plants.—W ooden labels for plants, to 
be inserted in the ground, may, it is said, be preserved for an indefinite 
time by first dipping them ia a solution of one part copper vitriol and 
twenty-four parts water, and subsequently immersing in lime water, or 
a solution of gypsum. 
