Note 24 — Chapter III

The experiment alluded to is one of a series by M. Plateau, who thus describes his arrangement of the fluid:—“We begin by making a mixture of alcohol and distilled water, containing a certain excess of alcohol, so that when submitted to the trial of the test tube it lets the small sphere of oil fall to the bottom rather rapidly. When this point is obtained, the whole is thrown upon filters, care being taken to cover the funnels containing these last with plates of glass; this precaution is taken in order to prevent, as much as possible, the evaporation of the alcohol. The alcoholic liquor passes the first through the filters, ordinarily carrying with it a certain number of very minute spherules of oil When the greater part has thus passed, the spherules become more numerous; what still remains in the first filters, namely, the oil and a residue of alcoholic liquor, is then thrown into a single filter placed on a new flask. This last filtration takes place much more slowly than the first, on account of the viscosity of the oil; it is considerably accelerated by renewing the filter once or twice during the operation. If the funnel has been covered with sufficient care, the oil will collect into a single mass at the bottom of the flask under a layer of alcoholic liquor.”—On the Phenomena presented by a free Liquid Mass withdrawn from the action of Gravity. By Professor Plateau, of the University of Ghent. Translated from the Memoirs of the Royal Academy of Brussels, vol. xvi.; in the Scientific Memoirs, vol. iv. part 13.