March 12, 1886.] 



SCIENCE. 



231 



most as injurious grapevine mildew, certainly no 

 debt of gratitude is owed to North America, not- 

 withstanding stringent laws, is widely extending 

 the fields of its devastation. A correspondent of 

 Nature states that it has already made its appear- 

 ance in the vineyards of Cape Colony. In a few 

 places the pest has been found in swarms, and 

 efforts are being made to stamp it out, or at least 

 hold it in check. Unfortunately the habits of the 

 insect are such that it is hardly possible that the 

 calamity threatening the grape-growing interests 

 there can be wholly averted. 



THE NAVAL OBSERVATORY. 



The report of the National academy of sciences 

 upon the naval observatory demands attention, 

 not only from all interested in scientific affairs, 

 but from those who desire only to see good ad- 

 ministration. In reading the report, the first 

 question to present itself to the mind of the candid 

 inquirer would be, How does it happen that the 

 national observatory of the country has remained 

 so long under the direction of superintendents 

 who were not astronomers, and whose profession 

 has little direct relation to its work ? A partial 

 answer to this question, from the naval point of 

 view, is found in letters addressed to President 

 Barnard by the present superintendent, and pub- 

 lished as an appendix to the report. In justice to 

 Commodore Belknap, we must say that his argu- 

 ments bear rather upon the question of the use- 

 fulness of the institution to the navy than upon 

 that we have just suggested ; but the two are so 

 closely related, that, in answering one, he evi- 

 dently intends to answer the other. It will there- 

 fore be interesting to examine his arguments, and 

 note then bearings upon the several points at issue. 



Commodore Belknap cites seven kinds of ser- 

 vices which the observatory renders to the navy. 

 A very slight consideration will, however, show 

 that every one of these services could be rendered 

 as well or far better by a national observatory 

 under civilian authority ; and, indeed, by an 

 establishment far more modest in its outfit than 

 even the present naval observatory, to say noth- 

 ing of the projected new one. The navy-yards 

 could get their time from the nearest railway-sta- 

 tion with ample accuracy for business purposes. 

 Naval ships in port could compare their chronome- 

 ters with signals from a national observatory as 

 well as the mercantile marine could, and any 

 superiority for naval purposes which might in- 



vest a time-signal tapped over the wires by the 

 hand of a commissioned officer might fairly be 

 deemed counterbalanced by the skill of a civilian 

 astronomer trained in this special business. The 

 naval chronometers could be kept, tested, and 

 rated at least as thoroughly at a national observa- 

 tory as they are at the present naval observatory. 

 Indeed, this is actually done at the Greenwich ob- 

 servatory, for all the chronometers purchased for 

 the British navy. It could be better done at the 

 Brooklyn navy-yard, whence most ships take then- 

 departure, by erecting and equipping a little ob- 

 servatory for this purpose at a cost of ten or 

 fifteen thousand dollars, thus saving the expense, 

 and danger to the rates of chronometers, incurred 

 by transporting them back and forth between New 

 York and Washington. 



That officers who had never worked in an 

 observatory till they went to take charge of one 

 would not find their task smooth satting, is to be 

 expected ; but we should never have anticipated 

 such a picture of difficulties of administration as 

 is held up by Commodore Belknap in one of his 

 letters which appears in this report. It seems that 

 Prof. Newcomb, in a letter to President Barnard, 

 drew attention to the curious fact, that during the 

 first twenty years of the existence of the observa- 

 tory, when two instruments, the transit and the 

 mural circle, were required to completely deter- 

 mine the position of a star, there was no concert 

 of action between the observers with these instru- 

 ments by which they should observe the same 

 stars. Commenting on this subject, Commodore 

 Belknap remarks, ' ' It may be considered as an 

 ideal state of things where two men of equal age 

 and upon equal footing (with no military ideas of 

 subordination) can engage in work upon two in- 

 struments, with but one clock and one chrono- 

 graph between them, and have every thing go 

 smoothly and without jealousy. The abandon- 

 ment of the too ambitious programme first laid 

 down was a matter of necessity, which it is 

 probable no one regretted more than the super- 

 intendent." 



To appreciate this picture, we have to reflect 

 that only one of the observers needed a chrono- 

 graph, and that the only use either of them had 

 to make of the clock was to look at it. We are 

 therefore led to infer, as the outcome of forty 

 years' experience, that under naval discipline it is 

 not found possible for two civilian astronomers to 

 take their time from the same clock without fric- 

 tion and jealousy ; that in consequence a well- 



