The Astrophysical journal . fa more simple nature : a wooden polar axis without clockwork,but furnished with a toothed wheel with 144 teeth in place ofan hour circle. The stars were allowed to trail over the plates,but every ten minutes the axis was advanced one tooth, so thatthe same field as before would still be covered. The axis wasfurthermore placed out of adjustment with reference to the pole,so that the successive star trails fell alongside each the time when any meteor appeared it is easy to referits trail to the position of the stars at that time. This instru-ment carrie
The Astrophysical journal . fa more simple nature : a wooden polar axis without clockwork,but furnished with a toothed wheel with 144 teeth in place ofan hour circle. The stars were allowed to trail over the plates,but every ten minutes the axis was advanced one tooth, so thatthe same field as before would still be covered. The axis wasfurthermore placed out of adjustment with reference to the pole,so that the successive star trails fell alongside each the time when any meteor appeared it is easy to referits trail to the position of the stars at that time. This instru-ment carried four cameras with similar portrait lenses of aboutfive inches diameter, and was in charge of Dr. Chase with anaid, while at the Observatory Mi. Brown, our secretary, , photographic assistant, and myself were on duty ; , of Ansonia, kindly aiding on one evening. Watch for the Leonids was kept on the nights of November12 to 16 inclusive. On November 12 it was clear from about 20 PHOTOGRAPHS OF THE LEONIDS 21. THE YALE OBSERVATORY METEOROGRAPH. 22 IV. L. ELK IN 16 hours on and plates were cxjjosed for about one hour in theObservatory instrument. Some fifteen Leonids were seen, butno trails secured. November 13 and also l5 were completelyovercast at New Haven all night, but the 14th and 15th wereclear throughout and the complete programme was carried out atboth stations. Plates were exposed from 11* 15 to about \]^20 each night, two in each of the Observatory cameras andthree in each of those at the secondary station — about twelvehours in all, therefore. On November 14 (|uite a display ofLeonids occurred, 118 being noted by the Observatory partybesides thirtv-six meteors from other radiants, while on Novem-ber 15 only thirty Leonids were noted against forty-two all these, some twenty-four were possibly in the field of thecameras, and up to now we have found nine trails on the Observa-tory plates and seven on those of Dr. Chases station, fourmeteors ha
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectspectru, bookyear1895
