262 . STATE HORTICULTURAL SOCIETY. 



KEROSENE EMULSION AND ITS USES. 



Bulletin No. 76, October, 1891. 



The Entomologist of the station is very glad to receive specimens of 

 insects, and will always answer inquiries regarding the same. Insects 

 should be sent by mail in close, strong boxes — tin or wood. Pasteboard 

 boxes are not strong enough, and are often crushed. Insects sent in 

 letters are almost always crushed beyond identification unless inclosed in 

 quills or capsules. The postage will not be more than one or two cents. 

 A little cotton ivith the insect will prevent jarring and breakage. In case 

 larvce, caterpillars, grubs, etc., are sent, some of their food-plants should 

 take the place of the cotton. This prevents shaking and supplies food. 

 No holes should be made to supply air. Any information regarding the 

 insects sent, will be greatfully received, and may prove very valuable — 

 inhere found; damage done; and any other facts. — A. J. Cook. 



This insecticide is becoming so important in the work of fighting our 

 insect foes, that any new facts concerning its manufacture and use will be 

 eagerly studied by every enterprising fruitgrower and farmer. We have 

 experimented very extensively this season and are glad to bring our results 

 to the attention of all interested in the warfare against insect pests. 



Before entering into the general discussion, I wish to correct my former 

 Bulletins, Nos. 58 and 73, in one or two points which further information 

 makes necessary. 



In No. 58 I stated what was then true, that so far as I knew, I was the 

 first to use and recommend a practical kerosene and soap mixture. I find 

 that one Henry Bird of Newark, N. J., as early as 1875, two years before 

 my discovery, advises mixing "a little korosene oil" with "strong soap- 

 suds." He adds " It readily combines and can be applied uniformly with 

 a syringe." This last statement makes it almost certain that he secured an 

 emulsion. He doubtless heated the soap to dissolve it (as I did two years 

 later) and used his syringe to mix, whereupon with the suitable propor- 

 tions "little oil and strong soap suds" an emulsion almost immediately fol- 

 lows. I find the above item in the Gardener's Monthly for 1875, p. 106. 

 In Bulletin No. 73 we say Dr. Riley's emulsion always fails with us. We 

 then used hard water from our artesian well as it was far more convenient. 

 With perfectly soft water it does not fail, which fact was first suggested 

 the past season by Prof. F. J. Niswander of Wyoming University, then an 

 assistant in our laboratory, whose valuable aid we wish to acknowledge. 



A good emulsion is one that is easily produced, and one in which the 

 kerosene oil will permanently unite with the emulsifying agent and not 

 separate upon dilution even if allowed to stand for days or weeks. As 

 water will always be the diluent, no formula is desired which will not give 

 success, when hard water is used in making or diluting our emulsion, as 

 often no other than hard water will be at our command. While ease and 

 certainty in forming our emulsion, and permanence of the mixture of the 

 kerosene with the emulsifying agent, are of first importance, after these are 

 positively secured the less the amount of the water used the better; as, in 

 case we desire to carry our emulsion some distance before use, we can delay 



