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THE POPULAR SCIENCE MONTHLY.

national scientific service contemplates the appointment of commissioners by the civil governments of the world. The deliberations of this body "would be the wisdom of the age; its recommendations would be respected by the legislative powers of the consenting and represented nations. Under its auspices all extra-limital astronomical, geological, and biological expenditures would be fitted out, and directed to those places which would be most fruitful for any particular purpose. The difference in the mental faculties between different nations would prevent the loss in such a body of any possible suggestion which the human mind could offer."

At the same meeting a paper was read by Profs. Grote and Pitt on new fossils in the collection of the Buffalo Society of Natural Sciences, from the water-line group. The free ramus of the chelate appendage of Pterygotus Cummingsi (G. and P.) was described by the aid of drawings. The crablike animal was over five feet in length, and lived in the shallow waters of the Silurian sea where Buffalo now stands. Its remains were deposited in the sedimentary lime-beds which are now being worked for manufacturing purposes.

 

Prof. Loomis on Rain-Areas.—The American Journal of Science for July contains the seventh paper of a series by Prof. Loomis, in which he investigates the phenomena of storms, their origin, development, and movements. It was shown in a previous paper that the form of a rain-area, that is, of a storm moving over the country, is usually elliptical: this elongated form is more obvious in storms which move along the coast than in those which move farther inland. The area of low barometer in a storm is not at the centre of greatest rainfall. Sometimes the rain centre is northward, or southward, or eastward, or westward, of the area of low barometer. North of latitude 36 the distance of the area of greatest rainfall from the centre of low pressure is in a majority of cases less than 250 miles, but in some instances three times that distance, the average being 300 miles. When extensive rainfalls occur there is a marked tendency to the formation of several centres of precipitation, and heavy rains may occur at various localities in a storm-area. This fact suggests that during the progress of a storm there occur local causes of great precipitation.

The tables show that heavy rainfalls are not of long duration over extended areas, and the conclusion from this fact is, that the causes which produce rain do not increase in force from the rainfall, but diminish and become exhausted. This result cannot be attributed to a want of supply of vapor, as the inflowing winds continually carry vapor into the storm-area, and this is especially true in the case of storms moving along the Atlantic border. What seems to be implied is, that an exhaustion occurs of the forces which impart that movement to the air requisite to precipitation.

The centre of great rain-areas occurs along the Atlantic border four times more frequently than inland, nor is this general fact changed in the region of the Great Lakes. Very extensive rainfalls are most frequent in autumn and winter, and occur most frequently in mornings and afternoons, and are least frequent during evenings, the difference in this respect being very marked. It is observed, too, that the "heaviest rainfalls are seldom accompanied by very high winds."

"There seems," says Prof. Loomis, "no room to doubt that areas of low barometer occur during periods of twenty-four hours with little or no rain, and travel nearly eastward with an average velocity of about twenty miles an hour." From this fact it is concluded that rainfall is not essential to the formation of areas of low barometer, and is not the principal cause of their formation nor of their progressive motion. The barometer is frequently low during the hazy weather of October, when the Indian summer prevails, a period usually of little rainfall.

 

Taste-Perceptions.—An interesting inquiry has been made by Vintschgau and Höingschmied to determine how much time is requisite to perceive different taste-sensations. We have already, in No. 39 of the Monthly, given the results obtained by these investigators in their earlier researches; but since then they have studied the subject more thoroughly, attacking