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peach trees, not stronger than 1 lb. to 300 gallons of water. The spraying upon 

 plum and cherry trees should be repeated two oi- three times, at intervals of about 

 ten days, as the curculio continues laying its eggs for some time. A most important 

 precaution that must be taken is to keep the mixture thoroughly stirred all the 

 time, or the heavy powder will sink to the bottom, and as the supply of liquid is 

 used up, it will be too strong at the bottom. London purple, one of the arsenical 

 compounds which is much used, I have found less satisfactory than Paris green, 

 from the fact that theareenicwhich it contains is in a much more soluble form, and as 

 London purple is a by-product in the manufacture of aniline dj'es, the amount of 

 this soluble ai'senic contained varies in amount in different samples, and the results 

 obtained are therefore uncertain. 



Another most useful remedy which has lately being brought into prominence is 

 the kci-osene emulsion, which can be used against all such insects as hibernate upon 

 the branches of fruit trees, as scale insects, aphides and bud-worms. It is difficult to 

 mix kerosene with water to dilute it ; it must first be emulsified and then diluted. 

 The usual formula is that advised by Prof. Eiley, the U. S. Entomologist, and con- 

 sists of ^ lb. soap, boiled in 1 gallon ofwater until it is quite dissolved; it is then turned 

 boiling hot into 2 gallons of kerosene, and is then churned by means of a syringe or 

 force pump for about 10 minutes, when the emulsion comes. The emulsion is then 

 to be diluted with nine times its quantity of water before using it. I have no doubt 

 that many of you have used these remedies, and I merely wish to bring them up 

 formally for discussion, believing that they form a subject of great interest to you 

 all. 



The President. — Mr. Fletcher's paper is now open for discussion. It is a very 

 large subject, and one of very great importance. 



Mr. Hamilton. — In what proportions should Paris green and kerosene emulsion 

 be mixed with water so as not to be injurious ? 



Mr. Fletcher. — There are various proportions recommended, some of them 

 much stronger than I have ever advised myself; but I have found good results can 

 bo got with the following proportions : Upon apple and plum trees, which will stand 

 a stronger mixture than pears or peaches: one pound of Paris green to 

 two hundred gallons of water. That is the proportion as to Paris green. I 

 have never recommended the use of London purple, because the strength is not 

 necessarily defined. London purple is a waste product, and the amount of arsenic in it 

 is not regular; but in Paris green, which is a manufactured article, made according 

 to a set formula, it is different, and if used in the proportion given, I think will be found 

 satisfactory. Some people recommend to use it stronger but I have found 

 that it gives satisfactory results with very few instances of injury. The 

 kerosene emulsion is made from two gallons of kerosene in one of water in 

 which half a pound of any kind of 'soap has been dissolved. This gives 

 you the emulsion, which must afterwards he diluted, one part with nine of 

 water. The soap is dissolved by boiling it in water, and when it is at the boiling 

 point youtake it off the fire and turn in the kerosene. It is then violently agitated 

 with a syringe or force pump, and in about five or six minutes you got an emulsion 

 like cream. After two or three minutes there is an apparent union, but this is not to 

 be ti'usted, because directly you put in the cold water it separates at once. After 

 it separates you may do a great deal of injury if you use it upon some plants. The 

 kerosene floats on the top and the soap and water stand below. The mixture must be 

 thoroughly emulsified. You test it on a piece of glass. If you can smear it over 

 the glass it is perfect. Then reduce it with nine parts of water to one of the 

 emulsion. This formula, which originated at Washington, has been given in 

 almost all the horticultural journals and also in my reports to the Department of 

 Agriculture which I shall be glad to send to any one who cares to have them. 



Mr. Henry. — Out in British Columbia some insect or disease has caused a great 

 many black spots on the young apple trees. It causes the death of a great many of 

 them. Of course, we are not informed in these things out there, and we would like 

 to know what the cause is that makes these black spots on the young apple trees. 

 We see them first early in the spring. 



