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Rh Spottiswoode, F.R.S., who, after calling attention to the great number of antique instruments present, dwelt upon the valuable services often rendered to science by earnest students possessed of very inadequate means. "In reviewing," he said, "the series of ancient, or, at least, now disused instruments, one thing can hardly fail to strike the attention of those who are accustomed to the use of the modern forms. It is this: how much our predecessors managed to achieve with the limited means at their disposal. If we compare the magnificent telescopes, the exquisite clock-work, the multiplicity of optical appliances now to be found in almost every private, and still more in every public observatory, with those of two centuries past; or, again, if we look at the instruments with which Arago and Brewster made their magnificent discoveries in polarized light, in contrast to those with which the adjoining room is literally teeming, we may well pause to reflect how much of their discoveries was due to the men themselves, and how comparatively little to the instruments at their command.

"And yet we must not measure either the men or their results by this standard alone. The character of the problems which Nature propounds varies greatly from time to time. First we have some great striking question, the very conception and statement of which demand the highest powers of the human mind. Next follow the first outlines of the solution sketched by some master-hand; afterward the careful and often tedious working out of the details of the problem, the numerical evaluation of the constants involved, and the reduction of all the quantities to strict measurement. It is in this part of the business that the more elaborate instruments are specially required. It is for bringing small differences to actual measurement that the complex refinements with which we are here surrounded become of the first importance. But happily this complication is not of perennial growth. In reviewing from time to time the various aspects of a problem in connection with the instrumental appliances designed for its solution, the essential features come out by degrees more strongly in relief. One by one the unimportant parts are cast aside, and the apparatus becomes reduced to its essential elements."

 

Franklin Institute of the State of Pennsylvania has opened a reception-room at the northwest end of the Machinery Hall, Centennial Exhibition grounds. The following objects of great historical interest have been placed in the room: 1. Franklin's electrical machine; 2. Oliver Evans's steam locomotive-engine, constructed in 1804; 3. Oliver Evans's high-pressure steam-engine, same date; 4. Working model of a steam-engine constructed by M. W. Baldwin, presented by him to the Franklin Institute, about the year 1832. Files of the industrial journals may be found here, and visitors will be cordially welcomed.

steps have been taken for holding an international horticultural exhibition and botanical congress in London in the year 1879.

made to the Silk-Merchants' Union of Lyons states the silk-crop of Europe in 1874 to have been, in round numbers, 9,050,000 pounds. The silk imported into Europe amounted to 11,500,000 pounds, most of it (8,000,000 pounds) coming from China. The greater part (6,000,000 pounds) of the domestic silk was produced in Italy.

in Herbert Spencer's "Principles of Psychology" will be given at Harvard University during the year 1876-'77, under the instruction of Prof. James.

the Pacific Medical and Surgical Journal a case is recorded of the conveyance of small-pox in a letter from Indiana to California. A man in the latter State received last December a letter from a sister in Indiana, staring that four members of her family had small-pox. A few days after the receipt of the letter, the man became ill, and the disease developed into a well-marked case of discrete variola.

the sugar-plantations of Natal the large python is employed to keep down rats and mice.

a late meeting of the St. Louis Academy of Science, Prof. C. V. Riley exhibited cocoons and spinning worms of the common mulberry silk-worm (Sericaria mori) reared on Osage Orange. The worms were a cross between the best French and Japanese races, and he had reared them for five years on Osage Orange with no reduction in quantity or quality of silk, and great increase of visor and healthfulness. 