13 
pastes. An analysis of a number of the powders shows that nearly all 
of them have borax as their chief constituent. This is sometimes 
mixed with meal, sometimes with flour, sometimes with sugar, some- 
times with Persian insect powder, sometimes with cloves, etc. The 
mixture is often colored with pink or blue dye stuffs. Nearly all could 
be prepared at home at one-half to one-tenth the cost of the store prep- 
arations. As to the pastes, all of these have from 1 to2 per cent of 
phosphorous as their poisonous principle. The remainder is sometimes 
molasses and corn meal or flour, and sometimes glucose sirup and corn 
meal or flour. 
BORDEAUX MIXTURE. 
Probably the most important of all fungicides is Bordeaux Mixture 
prepared by the action of lime suspended in water on a solution of 
copper sulphate (blue vitriol). It has been pointed out in Farmers’ 
Bulletin 38 of this Department that the way of mixing these two con- 
stituents has a very appreciable effect on the chemical and physical 
properties of the mixture. It was further pointed out that if both 
solutions are dilute when mixed, a product will be formed which will 
stay in suspension and adhere to the foliage much better than if both 
solutions were concentrated. There are now several firms putting up 
an article called ‘* Dry Bordeaux Mixture.” This article represents 
an attempt to supply the ready mixed Bordeaux Mixture to the con- 
sumer, but such an attempt can hardly be successful. In the first 
place, drying the mixture is a step farther than using concentrated 
fluids, so that the dry preduct obtained in such a way would have very 
different chemical characteristics from the mixture properly prepared. 
Again, when we dry the mixture the suspended particles become much 
coarser, so that when completely dry we would have a substance the 
principal part of which, i.e., the oxide of copper, would hardly stay 
in suspension at all, but would immediately sink to the bottom. 
“GRAPE DUST.” 
‘*Grape Dust” is an article put up for the treatment of diseases of 
the grape vine. It contains— 
Per cent. 
MG se eee et ee ee ao a oan claencietacecnknne 35. 00 
Ree Ee earns Soe wars he ne eicn ta en unas nea Ss Ceepmnssag keke wap os 60. 00 
CaM ORM ete reso eh oe Siig tip Soeinccins stem anes ahee sc . 90 
And 4 per cent (about) of other indifferent substances. 
Two of these constituents, i. e., sulphur and oxide of copper, are 
of course valuable for the purpose intended, but the 35 per cent of 
gypsum is of no value, and only adds weight. 
