No. 6. DEPARTMENT OF AGRICULTURE. 251 



The forumlii used by Mr. Marlatt is: 



Lime, unslaked (pounds), 30 



Sulphur, ground (pounds), 30 



Salt, stock (pounds), 15 



Water (gallons), 60 



The mixture was steam boiled four hours and applied hot. 



A great diversity of directions for preparing this wash appears in 

 the Pacific Coast publications; but the essential point is that there 

 must be a very thorough boiling for at least one hour. Two, three 

 or even four hours are often recommended and the mixture must be 

 hot* when applied. In all my conversation with Pacific Coast or- 

 chardists, this ''long boiling" was emphasized. 



Straining is always essential, and it should be noted that the wash 

 is very corrosive. Pump and hose should be most thoroughly washed 

 after using it and the hose will at best last only a short time. 

 Leather, rubber or cotton packing must be well looked after in all 

 cases. 



The price of this wash, aside from the labor involved, should not 

 exceed two cents per gallon and it may be applied at any time during 

 the winter. 



WHALE OIL SOAP. 



This was the material first successfully used in Maryland in fight- 

 ing the pernicious scale, and it can be usually depended upon for 

 good results when applied at the rate of at least two pounds in one 

 gallon of water. This is also a very caustic substance and cor- 

 rodes the scales upon which it is spread. As the scales thin out, the 

 moisture of the air dissolves the soapy coating and the mixture, in 

 time, soaks through the covering, coming into contact with the in- 

 sects belov/. Too much rain may wash off the soap before it has had 

 an opportunity to produce its specific effect, and the result will be 

 correspondingly incomplete. At any strength less than two pounds 

 in one gallon of water, the effect will not be sufiiciently complete and 

 the tendency has been rather in the direction of using two and one- 

 half or even three pounds of soap in the same quantity of water. 



This makes a nasty mess to spray, and it should be at least warm to 

 remain liquid enougli to pass readily through the nozzle. Great 

 thoroughness is necessary, that there may be material enough to 



•This not now regarded as essential for good effects; but the mixture sprays better when 

 warm. 



