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Tue Distance TO WHICH SMALL DISTURBANCES AGITATE A LIQUID. 
By A. Witmer Dorr. 
[Abstract. ] 
In the course of an unfinished piece of work on a new method for 
determining the viscosity of water, the following somewhat curious result 
was obtained: 
If a sphere of one centimeter radius hang from an arm of a balance 
by a long fine wire, and be immersed in a vessel of water, it may be 
caused to perform vertical vibrations of any desired extent and rapidity 
by suitably weighting the pans of the balance. The nearness of the sides 
of the vessel will be found to greatly affect the rate at which the vibra- 
tions die down. Even when the sides of the vessel are very distant, they 
have an appreciable effect. When the vessel is a large-sized carboy, the 
effect of the sides is still quite appreciable. That is to say, if a sphere of 
one centimeter radius perform one vibration for every fifteen seconds 
through a range of one centimeter in a mass of water, the effect on the 
water at a distance of a foot from the sphere is quite appreciable and 
measurable, the water being agitated to that distance instead of merely 
flowing round the slowly moving sphere to fill up the space it vacates. 
It may be added that the method referred to for measuring the vis- 
cosity of water is not intended as a practical method for finding the vis- 
cosity of different liquids, but merely as a means of contributing to the 
settlement of the dispute regarding the discordant values of the viscosity 
of water obtained by the several other methods that have been employed. 
THe EvApoRATION OF WATER COVERED BY A FILM OF OIL. 
By A. WILMER DUFF. 
{Abstract.] 
A vessel of water. covered by a film of paraffin oil 4 mm. thick and 
placed in a box artificially kept dry, lost 4 gms. of water in two months, 
while in another case in which the film of. oil was only 1 mm. thick the 
loss in two months was 11 gms. After considerable difficulty it was 
proven that this loss was not at all due to a passage of the water through 
