79 



think made a permanent mixture. Dr. C. V. Riley argues that I only made a temporary 

 mixture, which he says was made years before, although I have been unable to find the 

 record. Whether it were an emulsion or not, it was very successfully used, as success- 

 fully as in later years. That I appreciated the importance of the emulsio7i, or even recog- 

 nized it or produced it except as an accident, is not true. Messrs. Birnard, Hubbard, 

 and Riley did this as the result of extended experimentation, and heralded the facts forth 

 to the world, and I gladly accord to them the chief credit. 



As to Paris green, I believe my friend Hon. J. S. Woodward, of Lockport, N.Y., 

 was the first to announce it as a specific against the Codling Moth, which he did in the 

 autumn of 1878. He relates to me that he advised a neighbour to use it to destroy the 

 canker worms. The neighbour observed that the trees treated were very free from Codling 

 Moth larvse, and Mr. Woodward divined the cause. I had a very similar experience the 

 same year. Mr. J. W. Tafit, of Plymouth, Mich., came to me in 1878 with specimens of 

 canker worms, which he said were destroying his orchard. I advised Paris green, which 

 housed with the same results that greeted Mr. Woodward's neighbour. Mr. David Allen 

 reported the facts to me. I said, " Can it be possible that the poison has worked this 

 double benefit 1 1 will test the matter." Mr. Woodward had already announced his 

 belief in the matter. In 1879 I made the first careful te.st and proved by a most crucial 

 test that Paris green was not only a specific against the insect but safe to use. The 

 results of these experiments were given at the Boston meeting of the American Associa- 

 tion for the Advancement of Science, August, 1879. The results which I then socared 

 were remarkable beyond what may usually be expected or hoped for. This was because 

 I treated a small tree and took special pains that every fruit should receive the poison. As 

 great care to-day will meet with the same success. Thus while Mr. Woodward was 

 the first to suggest and announce this remedy, I was the first to prove and announce 

 positively that it is both safe and efi"ective. So far as I know I was also the first to 

 determine the best proportion — 1 pound to 200 gallons of water — and to show that 

 it is safe to pasture in an orchard at once after the poison is applied if the applici- 

 tion is properly made. 



AN EXPERIMENT WITH KEROSENE EMULSIONS. 



BY HERBERT OSBOEN, AMES, IOWA. 



The most satisfactory method of preparing the valuable kerosene emulsion is desired 

 'by all, and a comparative test made this season may be of interest. 



The first was a preparation in which the formula advocated by Professor Cook was 

 carefully followed, using the hard soap and not the soft soap formula, the materials while 

 still hot being thoroughly mixed with an egg beater. 



The result was that we had what appeared to be an excellent emulsion, but in a glass 

 jar we could soon see a separation taking place, the white emulsified part rising to the 

 top and the water or soapsuds gradually increasing at the bottom. This continued 

 until there was about two-thirds or a little more of soapsuds and one-third or less of 

 emulsion above it. 



While this at first could be readily mixed again a day later, the soapsuds in the 

 bottom had hardened into a jelly that when mixed with additional water would but 

 imcompletely dissolve and the clots included caused great inconvenience by clogging 

 the nozzle. 



The other preparation, made according to the usual formula for soap emulsion (the 

 Riley-Hubbard formula), emulsified and remained fixed with but a very few drops of 

 soapsuds gathering at the bottom, even after days of standing, showing that the pro- 

 D rtions were such that the soap water and kerosene balanced each other. This thick- 

 ened to a buttery consistence, but dissolved perfectly in water, and only a trace of oil 

 arose to the surface when thus mixed. 



