SCIENCE. 



the resources of the observatory, to continue its astrono- 

 mers and its instruments in the present situation. A 

 petition was presented to Congress (1878, Jan. 10), 

 from prominent men of science, asking for its removal, 

 and Jan. 16, 1878, a bill was introduced by Mr. Sar- 

 gent in the Senate, providing for the appointment of 

 a commission to select a suitable site. In the mean 

 time a plan for the new building had been prepared at 

 the observatory, submitted to all the prominent as- 

 tronomers of the country for their suggestions, corrected 

 and adopted. The report of the Commission, consist, 

 ing of Admiral Ammen, U. S. N., Colonel Barnard- 

 U. S. A., and Leonard Whitney, Esq., was made 

 1878, Dec. 7. It recommended the purchase of 

 " Clifton," a beautiful site of 45 acres in Georgetown, 

 situated on Rock Creek. 



Unfortunately, it was not learned until after the re- 

 port was made, that it had been seriously contemplated 

 to build a railway down the valley of Rock Creek. 

 This report was not acted on, owing to the fact that 

 the presence of a railway would seriously interfere with 

 the stability of the instruments. Therefore a new com- 

 mission was appointed Feb. 9, 1880, consisting of 

 Senator W. P. Whyte, Representative L. Morse, and 

 Admiral Rodgers, U. S. N., under a bill approved Feb. 

 4, 1880, which appropriated $75,000 to the purchase 

 and selection of a suitable site. The officers of the 

 Observatory were directed to examine the many sites 

 offered for sale. These lay in three different parts of 

 the city : first, north of the capital near the Soldiers' 

 Home Park, and near the Baltimore & Ohio Railroad ; 

 second, north of the main part of the city ; third, north- 

 west of the city, in Georgetown. The preferences 

 were for the sites in the first section. Each site that 

 was at all eligible was tried in the following way : the 

 fundamental observations depend upon the accurate 

 measures of the zenith-distances of stars. As the 

 zenith is not a visible point the nadir point (which 

 can be made visible, and which is directly op- 

 posite the zenith point) is chosen. A box of quick- 

 silver is placed immediately beneath the meridian 

 instrument and the position of the reflected images of 

 the spider lines of the instrument observed ; when 

 these coincide with the spider lines seen directly, the 

 instrument is vertical or it is pointing to the nadir. 

 Such observations as these have to be made at all 

 hours of the night and day, and anything that seri- 

 ously interferes with them will prevent the taking of 

 satisfactory observations. The question then was, to 

 try each of the proposed sites with this test and to 

 unhesitatingly reject any site which did not fulfill the 

 conditions. To do this a post was firmly planted in 

 the ground. On the top of this a flat basin contain- 

 ing quicksilver was placed. A telescope was directed 



towards the quicksilver about dusk, so that the image 

 of the pole star should be seen in the telescope. This 

 image usually showed as a neat quiet round disk. The 

 times of the passing of railway trains was known, and 

 at these moments the image of the star was watched. 

 For many of the places tried, the vibration of the 

 mercury surface caused by the tremors of the ground 

 was so great that no image of the star could be seen 

 for many minutes during the passing of the trains. 

 This was a fatal objection, since similar observations 

 may have to be taken at any moment of the night or 

 day. 



For those places near a public road the experiment 

 was varied by causing a loaded wagon to be driven 

 rapidly up and down. The experiments were always 

 made at least twice to avoid errors, and only those 

 places rejected which were plainly unsuitable on this 

 account. No matter what might be their other ad- 

 vantages, if they did not stand this test they were 

 useless for astronomical purposes. 



The places just north of the city were rejected on 

 account of the smoke always rising from the mass of 

 chimneys, an artificial and constant fog. In this way 

 the choice has been narrowed down to two places. 

 One directly south of the great park of the Soldiers' 

 Home and one in Georgetown. The first is so situ- 

 ated that to make it suitable for observatory purposes 

 a very large quantity of land would have to be bought ; 

 the second place can be bought with the appropria- 

 tion. The matter is in this condition at present. No 

 choice has been made by the commission as yet. 

 There is, of course, a great desire on the part of land- 

 owners to force the commission to buy land in their 

 neighborhood, but the choice must finally be made on 

 the principles heretofore adopted. The new Obser- 

 vatory is to stand for a century at least and no small 

 and petty personal considerations should be allowed 

 to enter. 



THE PRACTICAL VALUE OF SCIENCE. 



" I have endeavored to state the higher and more abstract 

 arguments by which the study of physical science may be 

 shown to be indispensable to the complete training of the 

 human mind, but I do not wish it to be supposed that be- 

 cause I maybe devoted to more or less abstract and unprac- 

 tical pursuits I am insensible to the weight which ought to be 

 attached to that which has been said to be the English con- 

 ception of Paradise — namely, 'getting on.' Now the value 

 of a knowledge of physical science as a means of getting 

 on, is indubitable. There are hardly any of our trades, ex- 

 cept the merely huckstering ones, in which some knowledge 

 of science may not be directly profitable to the pursuer of 

 that occupation. An Industry attains higher stages of its 

 development as its processes become more complicated and 

 refined, and the sciences are dragged in, one by one, to take 

 their share in the fray." — Huxley. 



