July 13, 1917] 



SCIENCE 



37 



predicted position, and as an object easily vis- 

 ible in medium-sized telescopes. Because the 

 comet was following its predicted path so 

 closely we decided not to squander money in 

 cabling the fact of its reobservation to Euro- 

 pean observers. Perrine observed his comet 

 morning after morning as weather permitted, 

 for fifteen days, until on February 14 a cable- 

 gram was received from Kiel, Germany, an- 

 nouncing that Lamp had reobserved Perriue's 

 Comet c 1895 that morning. The cablegram in 

 cipher code was received at the Lick Observa- 

 tory by one of the astronomers, in perfect 

 order as shown by the control word; but in 

 converting the cabled right ascension of the 

 comet from degrees and minutes of arc into 

 hours and minutes of time the translator made 

 an error of 24 minutes of time, equivalent to 

 6° of arc. The erroneous translation was 

 handed to Perrine. He compared this with 

 what he knew to be the real position of Comet 

 c 1895, by virtue of his observations in the 

 preceding half month, and saw that there was a 

 discrepancy of about 24 minutes of time. In- 

 asmuch as the check word in the cablegram 

 was correct he judged that the object observed 

 by Lamp in Kiel must be a different comet 

 from his own. The following morning was 

 clear and he pointed the 12-inch telescope to 

 the position that was handed to him. In look- 

 ing through the finder of the telescope he saw 

 an eighth magnitude comet in the field of view. 

 This did not surprise him. He observed the 

 position of the new comet, and we transmitted 

 the observation by telegraph and cable, as 

 usual, as belonging to a new comet discovered 

 by Lamp in Kiel. This new object was at once 

 known as Comet a 1896. Naturally consid- 

 erable mystery existed (see Astronomical Jour- 

 nal, Vol. 16, p. 56, 1896, and Astronomische 

 NachricUen, Vol. 139, pp. 365-66, 1896). Sev- 

 eral weeks elapsed before the tangled situation 

 was unravelled at Mount Hamilton by our 

 looking up the original cipher cablegram and 

 detecting the error of 24 minutes in the con- 

 version of arc into time, made after the cipher 

 message had been translated and checked. 



It is a surprising fact that the error should 

 have directed the telescope upon an unknown 



comet, but the surprise increases when we con- 

 sider another attendant fact. The new comet 

 was moving amongst the stars very rapidly; 

 more than 2° east in right ascension and more 

 than 3° north in declination, daily. When the 

 cablegram was written in Kiel on the morning 

 of the fourteenth the new comet was six or 

 seven degrees from the cabled position. When 

 the erroneous position was handed to Perrine 

 on the morning of the fourteenth the new 

 comet was three degrees from that position. 

 When the first opportunity came, the following 

 morning, to examine the erroneous position, 

 the rapidly-traveling comet had moved into 

 that position. Had the telescope been pointed 

 to that position on any other morning whatso- 

 ever, the celestial visitor would have been far 

 outside the finder field, and the chances are 

 fair that it would have come and gone un- 

 seen. The cabled Kiel position of reobserva- 

 tion of Comet c 1895 and Perrine's position of 

 Comet a 1896 were: 



Comet c 1895, Feb. 14, E. A. = 19 h. 45 m., 



Dec. ::= — 2° 23' (correct translation). 



Comet c 1895, Feb. 14, R. A. = 19 h. 21 m., 



Dec. = — 2° 23' (erroneous translation). 



Comet a 1896, Feb. 15, E. A. = 19 h. 22 m., 

 Dee. = — 2° 49'. 

 The angular radius of the finder field was 



about 1° .3. 



I doubt whether another case of coincidence 

 as remarkable as this one is on record in the 

 literature of astronomy. 



W. W. Campbell 

 Lick Obsekvatoet, 

 June 4, 1917 



REPORT OF DR. E. H. WILLIAMS ON THE 



FIRST PHASE OF PENNSYLVANIA 



GLACIATION 



When in 1880 Professor Lewis and myself 

 conducted the survey of the terminal moraine 

 across Pennsylvania (the results of which are 

 embodied in volume Z of the Second Geolog- 

 ical Survey of the State) we supposed at the 

 outset that we were following the actual limit 

 of glaciation. Soon, however, we were con- 

 vinced of our error and spoke of a " fringe "■ 

 of territory sparsely covered with glacial 

 markings, extending an indefinite distance 



