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SCIENCE 



[N. S. Vol. XXXI. No. 787 



in decimation is determined by observations of 

 cireumpolar stars at consecutive transits U. C. 

 and L. C. 



The sun and brighter stars are to be observed 

 daily in both right ascension and declination, and 

 the refraction by day and by night at all zenith 

 distances is to be separately investigated and 

 determined. 



Systematic observations are being made in both 

 right ascension and declination of lists about an 

 hour long in right ascension of cireumpolar stars, 

 culminating between five and seven o'clock p.m. 

 apparent local time, and of the same lists between 

 the same hours in the morning at consecutive 

 culminations as far as possible. These observa- 

 tions are made for fundamental places of the stars 

 themselves and for the determination of the lati- 

 tude and azimuth of the instrument and marks 

 and of the atmospheric refraction. The advan- 

 tages of observations of this kind are explained 

 in Science, Vol. XXV., p. 689. 



A group of nine fundamental stars near the 

 vernal equinox has been selected for use as the 

 fundamental standards in right ascension. They 

 are being observed in connection with another 

 group of stars near the autumnal equinox and are 

 to be connected with stars at all right ascensions 

 with a view to detect and determine systematic 

 errors in right ascension. This requires the ob- 

 servation of stars more than twelve hours apart 

 in right ascension on the same day by the same 

 observer, and the work is combined with the 

 observations of cireumpolar stars described above. 



16. On September 30, 1909, certain new canals 

 were observed on Mars at the Lowell Observatory 

 which proved to have an important history. The 

 discovery of new canals on Mars, i. e., some never 

 before seen, is nothing new, as some four hundred 

 have been detected there in the last fifteen years. 

 The present canals were remarkable in being not 

 only new to earth but new to Mars. This was 

 proved by reference to the records kept of the 

 observatory's observations since 1894. Not only 

 had they never been recorded before, but exam- 

 ination showed that they were not due to any of 

 the several causes which have been found there to 

 affect the visibility of the canals, to wit: seasonal 

 change, austral or boreal development, etc. They 

 had therefore never existed previously but had 

 just been formed. The importance of this dis- 

 covery needs no comment, except that it was only 

 made possible by the systematic, continuous re- 

 search of fifteen years. 



17. In the course of radial velocity work at 



Flagstaff, spectra of numerous stars in Scorpio, in 

 Perseus and in Orion have been found to contain 

 peculiarly sharp H and K calcium lines, which by 

 their character and behavior seem to originate in 

 inter-stellar space, according to Mr. Slipher. 



18. At the Dominion Observatory, Ottawa, per- 

 sonal equation with the registering micrometer 

 has been found to be not a negligible quantity. 

 The paper by Mr. Stewart deals with the observa- 

 tions of 1908, giving the relative personal equa- 

 tions of the five observers engaged, and describing 

 a short investigation into the causes underlying 

 the phenomenon. In the case of the author there 

 was found a tendency to set the movable wire 

 always to the left of the star by a quantity in 

 the neighborhood of a second of arc, depending 

 on the magnitude; north stars at upper culmina- 

 tion would thus be observed too soon, others too 

 late. 



19. Apparent discrepancies in Professor Very's 

 measures of the Lowell Observatory spectrograms 

 of Mars and the moon, on which Professor Camp- 

 bell has commented, are explained as due to the 

 mode of reduction. In spite of minor variations, 

 the mean readings for five plates gave for the 

 extra intensification of little a in Mars in con- 

 ventional units, a value nine times as great as 

 the probable error. No greater accuracy than this 

 is claimed, but the existence of water vapor in 

 the atmosphere of Mars is believed to be demon- 

 strated. The result is made possible by the su- 

 periority of Dr. Slipher's spectrograms. 



Campbell's claim that Professor Very's result 

 is due to a notable increase of telluric " a " 

 which happened to coincide with the taking of 

 the Mars spectrogram on each of five dates, is 

 examined and rejected. 



20. Simultaneous observations have been carried 

 on with the two instruments mentioned in the 

 title for the past five years; those for 1905-8 are 

 available for this comparison, embracing 931 de- 

 terminations. Confining our attention for the 

 present to the larger deviations, we find the fol- 

 lowing results for the two instruments: 



Both residuals 4 times the probable error, 2 

 (both like signs). 



Both residuals 3 times the probable error, 9 

 ( like signs, 8 ; unlike, 1 ) . 



Both residuals 2 times the probable error, 75 

 (like signs, 50; unlike, 25). 



The preponderance of like signs seems to leave 

 little doubt that anomalous fiuctuations of very 

 appreciable magnitude do occasionally take place. 



21. Mr. Campbell gave a rSsumS of the visual 



