INSECTICIDES AND GENERAL REMEDIES. 415 



is highly poisonous not only to insects but also to the higher forms of 

 life. When proper precautions are taken, however, there need be no 

 more danger in its use than in the employment of arsenical sheep-dips 

 or strychnine for other farm i)urposes. 



" It is desirable to have various sizes of the coverings ; and withal, 

 the initial outfit demands an outlay so considerable, that not every 

 orchardist will find it economical to provide himself with an equip- 

 ment for his sole use. But by co-operation among a number of 

 growers, the expense per tree treated may be lowered to a figure 

 which leaves a handsome margin of profit in the benefits which accrue 

 from the operation. After the first expense for the equipment the 

 chief item of cost is the labour, but this expense is not much, if any, 

 greater than the expense of spraying citrus-trees. When purchased 

 in large quantities the chemicals are not expensive. The cyanide 

 may be procured in London at lOd. per lb. in 224 lb. lots, and the 

 sulphuric acid in Cape Town for 50s. per case of 168 lb. : one mer- 

 chant sells the acid at 26s. per case of 122 lb. Estimating the 

 cyanide to cost Is. 6d. per lb. and the sulphuric acid 4d., the expense 

 of the chemicals necessary for a tree ten feet in height would be 

 about 3d." 



With reference to dressing the soil, various mixtures have been 

 used, but the one which has recently found most favour with prac- 

 tical men is Vaporite.^ It should be sown broadcast in the soil prior 

 to digging, and when thus applied it gives off" a vapour that destroys 

 the larvee of many insects, as, for example, wire-worm, leather-jackets, 

 and others which pass their larval stage in the soil. 



As regards spraying in the nursery, various commercial washes may 

 be used, and of course it may be noted that practical men will differ 

 in their opinion. It will therefore, perhaps, be best to give what 

 may be considered a kind of mixture which can be used with the 

 knapsack spraying arrangement or the hand syringe. 



Get an old boiler of, say, 16 gallons capacity. Boil about 7 gallons 

 of soft water; add and well mix in this about 10 lb. soft-soap, to- 

 gether with about 1 gallon of paraffin. Then boil in a separate vessel 

 about 5 lb. quassia chips. Strain and add to the above. This will 

 form a kind of stock solution, and when quite cold add and mix well 

 in about 100 gallons of soft water (three old paraffin casks), and apply 

 with syringe. 



1 There are several classe.s of a siiuilar preparation on the market. 



