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Show CALIFORNIA EARTHQUAKES, Number That Have Shaken the Stats During Ten Years, 1880, to 1808, Inclusive. Among tho reports ot the United States geological survey published in tho "nineties" ure eight bulletins on the subject of earthquakes In California, Califor-nia, which contain accounts of shocks that occurred during the ten yeaM from 1889 to 1898, Inclusive. Study of theso bulletins shows that there was hardly a single month in nil those ten years when seismic disturbances, moro or less severe, weie not felt along tho Pacific coast. The llrst of those bulletins (No. 08) was written by Prof. James Edward Keeler, astronomer In charge of earth-quako earth-quako observations at the Lick olnervatorry. Previous to this Prof. E. S. Iloldnn had published, through the California state printing olllce, a paper which contained n list of tho earthquakes that had occurod In California, Cal-ifornia, lower California. Oregon and Washington territory and which gnve all the available data up to tho end of tho year 1SS8. The next bulletin (No. 95) published by the geological survey was prepared by Prof, lloldcn. It contained nn account of the earthquakes earth-quakes In 1890 and 1S91. The other bulletins covering the records for 1892, 1803, 1S9I, 1895. 1890, 1897, nnd finally 1S98, wero published as bullotlns Nos. ,112, Hi, 129. 147. 155, nnd 1(11. respectively, respec-tively, and all were prepared by Prof. Charles I1- Pcrrlne of the Lick observatory. ob-servatory. ' The largest and most complete" Instrument used for recording cnrt.li-quakes cnrt.li-quakes on Mount Hamilton, ns do-scribed do-scribed In theso bulletins, records tho north and south, cast and west, and vortical components of the earth's motion separately on a smoked glass plate, which Is started by the prelim. Inary tremors of the enrthqunko and rotates uniformly In about thrco minutes, min-utes, the edge of tho pinto being grail, uated Into seconds nt the same tlmo by a clock, which also serves to record tho time of occurrence ot the shock. This instrument hns been called tho Ewlng seismograph. Another simpler form consists of a heavy "duplex" pen-lulum pen-lulum adjusted to a long period ot vibration, with a magnifying pointer or pen. which records on a smoked glass plato both horizontal components of tho motion. The vertical components compo-nents nnd tho time nro not recorded. Tho observatory possesses other seismographs seis-mographs of various patterns, but they aro not constantly In uso. |