SWEDISH WEIGHTS, Used by Bergman and Scheele.
- The Swedish pound, which is divided like the English apothecary, or troy pound, weighs 6556 grains troy.
The kanne of pure water, according to Bergman, weighs 42250 Swedish grains, and occupies 100 Swedish cubical inches. Hence the kanne of pure water weighs 48088.719444 English troy grains, or is equal to 189.9413 English cubic inches ; and the Swedish longitudinal inch is equal to 1.238435 English longitudinal inches.
From these data, the following rules are deduced 1. To reduce Swedish longitudinal inches to English, multiply by 1.2384, or , divide by 0.80747.
2. To reduce Swedish to English cubi cal inches, multiply by 1.9, or divide by 0.5265.
3. To reduce the Swedish pound, ounce, dram, scruple, or grain, to the corresponding English troy denomina tion, multiply by 1.1382, or divide by 8.786.
4. To reduce Swedish kannes to Eng ' lish wine pints, multiply by .1520207, or divide by 6.57804.
5. The lod, a weight sometimes used by Bergman, is the 32d part of the Swed ish pound : therefore, to reduce it to the English troy pound, multiply by .03557, or divide by 28.1156.
Universal Standard ,for Weights and smvs.
This is an object of vast importance, could it be attained : we fear, however, that, like a project for universal peace and good-will among men, it is a thing rather to be desired than expected, in the pre sent state of things. Philosophers may speculate on the importance and excel lence of such a scheme, but statesmen busy in projects of ambition, have not leisure to attend to any thing that does not augment their power, extend their influence, and render them rather a ter ror to mankind, than the objects of their praise and veneration. It behoves us, however, to give, in few words, a sketch of what has been attempted with a view to an universal standard for weights and measures through the whole world. The plans laid down have been deduced from philosophical princi pies. After the inven tion of pendulum clocks, it occurred that the length of a pendulum which should vibrate seconds, would be proper to be made a universal standard for length, whatever the denomination should be fixed on, whether yard, or any thing else.
It was however found, that it would be difficult in practice to measure and deter mine the true length of such a pendulum, that is, the exact distance between the point of suspension and the point of oscil lation. Another cause of inaccuracy was afterwards discovered, when it was found that the second's pendulum was of differ ent lengths in all the different latitudes, owing to the spheroidal figure of the earth, (see Riarrn,) which is the cause why places, in different latitudes,- at dif ferent distances from the centre, and of course the pendulums, are acted upon by different force's ofgravity, and therefore require to be of different lengths. In the latitude of London this is found to be 39-k inches nearly.
The Society of Arts, &c. have offered premiums for a plan that might accom plish this great object : and among other devices then brought forward was one by Mr. Hatton, which consisted in measuring the difference of the lengths of two pen dulums at different times of vibration, which could be performed more easily and accurately than that of the length of one single pendulum. This method was put in practice, and fully explained and illustrated by the late Mr. Whitelirst, in his attempts to ascertain an universal standard of weights and measures. The same kind of inaccuracy of measurement obtains in this way, though in a smaller degree, as in a single pendulum. Another method ,has been proposed, on observing very accurately the space that a heavy body falls freely through in one second of time. Here absolute accuracy is almost unattainable ; besides, the form of the earth introduces difficulties, owing to the different distances from the centre, and the consequent diversity in the force of gravity by which the body fills. This space, in the latitude of London, has been found 193 inches, of course it is different in other latitudes. The method of late years, proposed by the French, is that of measuring a degree on the earth's sur face, at the latitude of 45 degrees, and from this to deduce an universal measure of lengths, which would be easily appli cable to weights also.