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recommending the use of kerosene of any sort. He was of the opinion 
that the variation would be just as great in the crude article as in the 
refined. 
Mr. Hopkins said that in West Virginia they have a great variety 
of petroleum, from that as thick and black as molasses to the thin 
light-colored product. The oil obtained from the Standard Oil Com- 
pany is a mixture of all kinds except the heavy oil. The heavy oil is 
used for lubricating machinery. He had obtained some results which 
are quite at variance with the testimony of others and shows what 
conflicting results can be obtained in different States. In one case he 
recommended crude petroleum as an experiment in a large orchard 
which was almost dead from the scale and which the owner refused to cut 
down. It had been sprayed once with pure kerosene, which did some 
damage and killed many scales, but the owner had allowed it to go with- 
out treatment and the scales had again covered the trees. He sprayed 
it with crude petroleum obtained in Baltimore. When he last saw the 
orchard, in April, the trees were black and greasy, but underneath 
the bark they were as healthy as ever, the leaves were coming out in full, 
and the owner claimed that the crude petroleum had benefited them. 
He was not recommending the oil, but simply giving this as an exam- 
ple. His spraying was done in February and wherever the oil touched 
the bark it remained dark and greasy for months afterwards. A thor- 
ough examination failed to reveal any of the living scales, and he 
believed that the young scales could not settle and live on the oily 
surface. He felt very much encouraged. It is one of those problems 
which require cooperative work. As a result of further investiga- 
tion, he thinks it may become one of the best insecticides ever discoy- 
ered. He could not think of any better work than trying to find the 
reasons for the great difference in results in experimental work with 
insecticides. 
Mr. Webster said he was unable to see what could be gained even 
if crude petroleum should be perfected. It was true that we will have 
to get something cheaper and more effective than whale-oil soap, which 
if used on peach trees except during the winter will destroy the fruit, 
but in view of the difficulty he had had in getting crude petroleum 
and the high price asked for it, how much better an insecticide than 
whale-oil soap would we have even if it was perfected? He thought 
that entomologists who cared for their reputation would experiment 
much and say little for publication, for the present at least. He fur- 
ther stated that while experimentation was always in order, it would 
be best to stick to the whale-oil soap until more obscurities in regard 
to the use of petroleum had been eliminated. | 
Mr. Johnson said he agreed with Mr. Webster. We have got to get 
something better than kerosene for both peach and plum. In one 
instance he had sprayed an orchard of two hundred 9-year old peach 
