360 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1910. 



We will content ourselves with saying that we Frenchmen, born 

 bureaucrats and believing ourselves without rivals in the routine of 

 administration, would certainly find much to learn here from a prac- 

 tical point of view. 



All these researches on variable stars, upon stellar spectra and 

 their classification, may appear to the ordinary reader very monoto- 

 nous and of very little use; yet they are of great importance for 

 a knowledge of our universe. We should not forget that by means 

 of this incessant comparison these observers can often announce the 

 new stars (novas) which are so interesting in many ways. And yet, 

 further, a new short-period variable, a new type of stars gives cer- 

 tainly a new clue to the elucidation of yet unsolved problems or what 

 amounts to a new instrument for research in this vast laboratory of 

 the sky where new tools are rarely obtained. 



THE LICK OBSERVATORY. 



Now, crossing the whole continent from one shore to the other 

 and going to the Lick Observatory, we find a totally different estab- 

 lishment ; more grand because of the vastness of the means at its dis- 

 posal as well as notable for the beauty of its situation. Founded 

 through the generosity of James Lick, a rich California!!, and now 

 under the eminent direction of Prof. W. W. Campbell, the Lick Ob- 

 servatory is situated on Mount Hamilton, at an altitude of 1,400 

 meters, a beautiful site, although unfortunately somewhat difficult of 

 access despite its nearness to San Francisco. The distance from the 

 nearest railroad station to the peak is some 40 kilometers, over a rather 

 rough route, though suitable for an automobile. So the astronomers 

 must dwell there all the time, and during the winter this region must 

 lose some of its charms. 



We will dwell but little on the great Lick equatorial, one of the 

 most justly famed telescopes of the Avorld. Its focal length is 17.30 

 meters and its aperture 91 centimeters (36 inches). It may be used 

 for visual observations and adapted for photography by the aid of a 

 correcting lens placed just inside the focus. One of the most remark- 

 able aids used with this instrument, the only rival of which is at the 

 Yerkes Observatory, where it is further perfected, is the moving floor, 

 which may be raised by hydraulic means so that the observer, his 

 assistants, and all which surrounds him may be placed at a suitable 

 elevation. 



The great telescope is used for various researches, notably for 

 spectroscopy and the determination of radial velocities. The con- 

 struction of the spectroscope, known as the Mills spectrograph, was 

 most carefully designed. It has three prisms and an adjusting device 

 which assures the parallelism of the optic axis of the telescope to that 



