Scientific American Supplement, No. 508, September 26, 1885 eBook

This eBook from the Gutenberg Project consists of approximately 130 pages of information about Scientific American Supplement, No. 508, September 26, 1885.

Scientific American Supplement, No. 508, September 26, 1885 eBook

This eBook from the Gutenberg Project consists of approximately 130 pages of information about Scientific American Supplement, No. 508, September 26, 1885.
directly with the one that follows it, and with the rest through that, but that it is directly associated with all that are near it, though in unequal degrees.  He first measured the time needed to impress on the memory certain lists of syllables, and then the time needed to impress lists of the same syllables with gaps between them.  Thus, representing the syllables by numbers, if the first list was 1, 2, 3, 4 ... 13, 14, 15, 16, the second would be 1, 3, 5 ... 15, 2, 4, 6 ... 16, and so forth, with many variations.

Now, if 1 and 3 in the first list were learned in that order merely by 1 calling up 2, and by 2 calling up 3, leaving out the 2 ought to leave 1 and 3 with no tie in the mind; and the second list ought to take as much time in the learning as if the first list had never been heard of.  If, on the other hand, 1 has a direct influence on 3 as well as on 2, that influence should be exerted even when 2 is dropped out; and a person familiar with the first list ought to learn the second one more rapidly than otherwise he could.  This latter case is what actually occurs; and Dr. Ebbinghaus has found that syllables originally separated by as many as seven intermediaries still reveal, by the increased rapidity with which they are learned in order, the strength of the tie that the original learning established between them, over the heads, so to speak, of all the rest.  It may be that this particular series of experiments is the entering wedge of a new method of incalculable reach in such questions.  The future alone can show.  Meanwhile, when we add to Dr. Ebbinghaus’ “heroism” in the pursuit of true averages, his high critical acumen, his modest tone, and his polished style, it will be seen that we have a new-comer in psychology from whom the best may be expected.—­W.J., Science.

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SINKING OF THE QUIEVRECHAIN WORKING SHAFT.

The sinking of mine shafts in certain Belgian and French basins, where the coal deposit is covered with thick strata of watery earth, has from all times been considered as the most troublesome and delicate, and often the most difficult operation, of the miner’s art.  Of the few modern processes that have been employed for this purpose, that of Messrs. Kind and Chaudron has been found most satisfactory, although it leaves much to be desired where it is a question of traversing moving sand.  An interesting modification of this well-known process has recently been described by Mr. E. Chavatte, in the Bulletin de la Societe Industrielle du Nord de la France.  Two years ago the author had to sink a working shaft at Quievrechain, 111 feet of which was to traverse a mass of moving and flowing sand, inconsistent earth, gravel, and marls, and proceeded as follows: 

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Scientific American Supplement, No. 508, September 26, 1885 from Project Gutenberg. Public domain.