REPORT OF THE CHEMIST 151 



SESSIONAL PAPER No. 16 



3. By tlie use of freshly slaked lime less time is needed for the churning in order 

 to bring the mass to a perfect emulsion. Two to three minutes of vigorous, continuous 

 pumping were found sufficient. 



4. It is not apparently a matter of much moment that the lime be dry when mixed 

 withvthe kerosene. Excellent emulsions have been made when the slaked lime has been 

 quite moist or even made into a thick cream with water before adding the kerosene. 



Flour Emulsion. — It occurred to the writer that as good quicklime was not always 

 obtainable at a moment's notice, it would be well to ascertain if flour — to be had every- 

 where — would not answer equally well. Our experiments showed that flour could be 

 successfully substituted for lime in making the emulsion when desired for immediate 

 use. One pound to 1 quart of kerosene makes a perfect emulsion, as in the case of 

 Ihe lime, but 8 ounces were subsequently found sufficient to hold in perfect suspension 

 the quart of kerosene. 



The preparation with flour is very simple. The requisite amount of kerosene is 

 placed in the vessel (pail or barrel), which is preferably dry, and flour added in the 

 proportion stated, viz. : 8 ounces to 1 quart, the mass thoroughly stirred and the water 

 added — 2 gallons for every quart of kerosene. This is then vigorously churned, as 

 already described, say, for 5 minutes, and the emulsion is ready for use. 



It was further found that by scalding the flour a less weight is required. An 

 excellent emulsion which did not show the slightest separation of kerosene after one 

 week was prepared by scalding 2 ozs. of flour, mixing the resulting thin paste with 1 

 quart of kerosene and emulsifying with 2 gallons of water. 



The flour emulsion is smooth, easily atomized, and does not clog the nozzle. Any 

 separation into layers may be easily remedied by simply stirring or shaking the mix- 

 ture. It is equally effective, we believe, as an insecticide with the lime-formed emul- 

 sion, and amongst other advantages that may be claimed for it is the fact that there 

 is no perceptible whitening of the foliage, and, further, that in some places it will be 

 found cheai>er and easier to make than the lime emulsion. Its use is suggested as an 

 alternative when good lime is unobtainable — when the emulsion is for immediate use 

 and when intended for ornamental trees and shrubs, upon which the whitening of the 

 foliage is objectionable. 



FORMALIN — FORMALDEHYDE 40 PER CENT. 



The amount of Formalin used in the treatment of grain, especially wheat and 

 cats, for the prevention of smut, increases yearly and very rapidly. In Manitoba and 

 the North-west generally it has already very largely replaced bluestone, due no doubt 

 in a measure to the ease with which the solution may be prepared— simple dilution 

 being all that is necessary. The results of the Formalin treatment have been highly 

 satisfactory, and there is ample proof that Formalin is a most efficient smut destroyer. 

 It has been used in two strengths: 3 ozs. to 10 gallons (2 parts in 1,000), and 44 ozs. 

 to 10 gallons (3 parts to 1,000). The seed grain is either thoroughly sprinkled or im- 

 mersed for 5 minutes. In the majority of cases, and save perhaps with very badly 

 affected grain, the weaker solution has proved as effective as the stronger, and thorough 

 sprinkling equally satisfactory with immersion. In addition to ascertaining the 

 strength of several brands of formalin on the market, we have endeavoured this year 

 to learn if formalin, which had become milky through age, had lost its efficiency, 

 wholly or in part, and if such altered (polymerized) formalin injuriously affected the 

 germ of the grain. Tbese were questions asked by several correspondents in the ISTorth- 

 v/est last spring. A further enquiry' was as to the effect of the formalin treatment on 

 the vitality of wheat as compared with that of bluestone. 



