Page:Popular Science Monthly Volume 36.djvu/291

Rh movements in each second. Such were the transmissions outward. And all those were conditional on consciousness of the position of each hand and each finger before it was moved, and, while moving it, of the sound and the force of each touch. Therefore there were three conscious sensations for every note. There were seventy-two transmissions per second, one hundred and forty-four to and fro, and those with constant change of quality. And then, added to that, all the time the memory was remembering each note in its due time and place, and was exercised in the comparison of it with others that came before. So that it would be fair to say that there were not less than two hundred transmissions of nerve force to and from the brain outward and inward every second, and during the whole of that time judgment was being exercised as to whether the music was bring played better or worse than before, and the mind was conscious of some of the emotions which the music was intended to inspire.

Ancient Chaldean and Modern Measures.—According to Prof. Harkness, in his presidential address to the Philosophical Society of Washington, the ancient Chaldeans used, primarily, the decimal system of notation, and also the duodecimal in the division of the year and of the day into hours, and the sexagesimal in the division of the circle and of the hour and minute. The last two systems were also applied to weights and measures, and impressed upon them by the scientific authority of those ancient sages. "Now observe," says the author, "how the scientific thought of to-day repeats the scientific thought of four thousand years ago. These old Chaldeans took from the human body what they regarded as a suitable unit of length, and for their unit of mass they adopted a cube of water bearing simple relations to their unit of length. Four thousand years later, when these simple relations had been forgotten and impaired, some of the most eminent scientists of the last century again undertook the task of constructing a system of weights and measures. With them the duodecimal and sexagesimal systems were Out of favor, while the decimal system was highly fashionable, and for that reason they subdivided their units decimally; but they reverted to the old Chaldean device for obtaining simple relations between their units of length and mass, and to that fact alone the French metric system owes its survival. Every one now knows that the metre is not the ten-millionth part of a quadrant of the earth's meridian, and in mathematical physics, where the numbers are so complicated that they can only be dealt with by the aid of logarithms, and the constant π, an utterly irrational quantity, crops up in almost every integral, mere decimal subdivision of the units counts for very little. But in some departments of science, as, for example, chemistry, a simple relation between the unit of length (which determines volume), the unit of mass, and the unit of specific gravity, is of prime importance; and wherever that is the case the metric system will be used. To engineers such relations are of small moment, and, consequently, among English-speaking engineers, the metric system is making no progress, while, on the other hand, the chemists have eagerly adopted it. As the English yard and pound are the direct descendants of the Chaldean-Babylonian natural cubit and mina, it is not surprising that the yard should be only 0·48 of an inch shorter than the double cubit, and the avoirdupois pound only 665 grains lighter than the Babylonian commercial mina; but, considering the origin of the metric system, it is rather curious that the metre is only 1·97 inches shorter than the Chaldean double royal cubit, and the kilogramme only 102 grains heavier than the Babylonian royal mina. Thus, without much exaggeration, we may regard the present English and French fundamental units of length and mass as representing respectively the commercial and royal units of length and mass of the Chaldeans of four thousand years ago."

Mount Roraima.—Mount Roraima, that sharply perpendicular elevation in Guiana which so long defied attempts to reach its summit, has been ascended twice since it was first conquered by Mr. Im Thurn in 1884—by Mr. F. Dressel and Mr. Cromer, in October and November, 1886. While Mr. Im Thurn's ascent took place at the beginning of the rainy season, Mr. Dressel's was in the dry season, and their respective observations were marked by corresponding differences.