REPORT OF THE CHEMIST. ■ 187 



SESSIONAL PAPER No. 16 



acteristics of asafoetida. Experiments show that from 10 to 23 per cent of asa- 

 fcetida, accoi-ding to the quality of the substance, is soluble in carbon bisulphide. I 

 think we are, therefore, justified in supposing that the difference already referred to 

 is largely due to the presence of this gum-resin, and that Arborine is essentially a 

 mixture of ochre, sulphur and asafoetida. 



Eegarding its ejBBciency, we have no data to bring forward. Most probably, it 

 acts as au excellent deterrent against the attacks of certain forms of life, protecting 

 the tree by virtue of its sulphur, and possibly to a still greater extent by reason of 

 the peculiarly unpleasant and penetrating odour that it emanates, due to its asa- 

 foetida. We can only remark that the price asked for this material seems to be greatly 

 in advance of the cost of its components. 



WEED KILLING COMPOUNDS. 



HARVESTA CHEMICAL COMPOUND A WEED DESTROYER. 



This is a brownish coloured fluid, made in New Orleans, La., and sold for the 

 purpose of destroying weeds in gravel paths. It was analysed at Dr. Fletcher's request. 



The mixture was neither caustic nor alkaline, and on analysis was found to con- 

 tain arsenite of soda and common salt. These together amounted to 4-0 per cent, or 

 6 "4 ounces per gallon ;, the common salt being i '69 per cent, or 2 '7 ounces per gallon. 



No doubt this is an effective weed exterminator, since both its constituents have 

 long been known and used for this purpose. It is, perhaps, scarcely necessary to point 

 out that such preparations should only be used on paths or where it is desired to kill 

 all vegetation. 



WEED KILLING COMPOUNDS. 



For those who desire to prepare for themselves a weed-killing fluid we furnish the 

 following recipes. The fluids are cheap and easily prepared, and have been used with 

 good effect : — 



1. — To boiling water add common salt at the rate of one pound to one gallon. 

 As soon as the salt is dissolved, and the liquid is still hot, apply it by means of a 

 watering can. 



2. — White arsenic pounds 1 



Washing soda " 2 



Water gallons 3 



Boil and dilute with from two to three times its volume of water. Apply while 

 still warm in fine weather. This solution is highly poisonous. 



3. — Blue vitriol (bluestone) pounds 2 



Water (hot) gallons 6 



Put the bluestone in a crock or wooden tub and pour on the water. Use while 

 still hot. 



4. — Sulphuric acid in the proportion of one part of acid to 1,000 of water has 

 also been effectively used where the soil does not contain an?/ appreciable amount of 

 carbonate of lime. If there is effervescence when the acid solution is sprinkled on the 

 path (showing the presence of carbonate) this preparation will be of no value. 



5. — Salt cake, or acid sulphate of soda, a by-product in the manufacture of 

 muriatic acid, applied in solution (one pound to one gallon) is very effective. 



With respect to the use of any of the foregoing, it may be pointed out that 

 thorough applications, especially at the beginning of the season, are to be advised, 

 rather than lighter and more frequent doses. All these chemicals will do serious 

 injury to soils intended for cultivation. 



