28 
trees in February with 25 per cent kerosene and not a tree was living 
on the 28th of April last. He was at present making midsummer 
experiments. It seemed to him that atmospheric conditions were at the 
bottom of the difficulty and he thought it would be necessary to go 
back to the old whale-oil-soap remedy which destroyed the scale more 
effectively and was less liable to injure the trees. It would not be 
wise to substitute crude petroleum for whale-oil soap. After three 
years experience with kerosene, whale-oil soap, and gas he was of the 
opinion that there are other conditions which must be studied more 
seriously in the future than in the past, and he heartily agreed in the 
opinion of the chairman that cooperation is desirable. He believed it 
would produce better results in the future. We must not confine our 
labors to the territorial boundaries of a State but go outside for infor- 
mation, suggestions, and the experience of others. 
Mr. Fletcher stated that he was glad to hear what had been said 
about whale-oil soap and crude petroleum. He had never yet been 
able to see what object there was in trying to use petroleum. The 
results were too conflicting and always unsatisfactory, and the question 
of cost in the destruction of the apparatus was never considered. 
There was very slight injury to the hose in the use of potash whale-oil 
soaps, which could now be obtained of pretty uniform manufacture, 
and had been giving good results. These are always to be had and 
easy to get to most places. You can be sure of getting your whale-oil 
soap within a week or ten days, while he had found there was consid- 
erable difficulty in getting crude petroleum. He was of the opinion 
that there is room for experiment with much weaker mixtures of the 
potash soaps during the summer. His experience had been in favor 
of the potash soaps in preference to the crude petroleum or kerosene 
mixed with water. Even with the old kerosene emulsion there is some- 
times unexpected injury to trees, which was always put down to differ- 
ence in the oil or in the water. He was satisfied for the present that 
the whale-oil soap was the safest remedy; at any rate, it is the safest 
for those who are official entomologists, and have to recommend formulee 
to people who will make a mistake if they possibly can. 
Mr. Sanderson stated that he had not had much experience with 
crude petroleum, but so far his experience has been favorable. He 
sprayed an orchard of one hundred trees on the Delaware River with 
crude petroleum in the latter part of January, on a cloudy day, witha 
little hail and rain soon afterwards. The trees were mainly Bartlett, 
Kieffer, and Manning pears, which had been sprayed the year before 
with pure kerosene and somewhat injured, but which had recovered. 
Two months later, in March, he sprayed another lot of one hundred trees 
with 25 per cent solution of crude petroleum. It was a very windy 
day, and almost all the trees previously sprayed got a dose of the 25 per 
cent solution on one side. Examination shows no injury on either lot. 
