540 REPORT— 1901. 



participatiug in the work, who had not profited by the lessons of the past ; and One of 

 them read out a rather elaborate resolution for deciding one of the points in question 

 on a uniform plan. It was just such a resolution as would have led to an excited 

 debate at the earlier Conferences and ultimately to a cut-and-dried rule. It was 

 now received in embarrassed silence. Then one who had gauged the opinion of 

 the meeting more adequately rose to point out how retrogressive it was. With 

 the utmost courtesy to his colleague and in the most genial manner he pointed out 

 that such a resolution was both dangerous and useless, and was better let alone, 

 ■which was accordingly done. 



Again, one of the co-operating directors rose to ask for guidance on a doubtful 

 point. There were certain plates which might or might not be considered pro- 

 perly falling to his share, according to the definition of his boundary. In this case 

 individual opinion was deliberately subordinated to the decision of the meeting. 

 Would the meeting plea.^e decide the point ? Surely here the meeting might give 

 a decision without danger. But the meeting had been humbled, and was no longer 

 in the mood to give decisions. Proposals to direct the questioner to take the 

 doubtful plates, lo recommend him to do it, and to encourage him to do it, were 

 successively considered and rejected as being too dictatorial ; and it was finally 

 decided that the meeting would not forbid him to take the extra plates if he so 

 ■wished ! 



But the comedy of this result has a very serious significance. W^e may heartily 

 congratulate ourselves that the time is not yet come when astronomers are pre- 

 pared to lose their individuality in a co-operative scheme of work ; and still more 

 that such schemes can be found where such loss of individuality is unnecessary. 

 May it not be said that something very similar has been realised in the case of the 

 other scheme of co-operation referred to by the President of the Association 

 yesterday, the scheme for a Catalogue of Scientific Literature ? The original 

 proposals were of a kind which left too little scope for the individuality of the 

 different sciences. Fortunately the mistake was rectified promptly, and the present 

 plan leaves much more to individual judgment. Some such compromise would 

 seem to be essential (if we are not generalising too hastily) to the success of 

 co-operative enterprises in science. W'e must, above all things, take care not to 

 crush individuality. I would even go so far as to say that so much of the element 

 of competition as can be preserved without endangering uniformity in essentials 

 ■should be diligently cultivated. Add that the original scheme should be as modest 

 88 possible, and that an energetic man should be put in a position to wake up the 

 dilatory and to ensure that the pace, which is necessarily that of the slowest, be 

 not funereal, and I venture to think that we may eliminate failure from co-operative 

 scientific enterprises. 



The following Papers were read : 



1. Oil the Possibility of Systematic Error in Photoymphs of a Moving 

 Object. By A. R. Hinks, M.A. 



An a jinori objection to the method of obtaining the position of a planet from 

 photographs is the alleged possibility of systematic error due to the fact that the 

 images either of the stars or the planet must be short trails, and the ends of 

 these trails may not be symmetrical with respect to the mean epoch of 

 exposure. In photographing Eros at Cambridge last winter for the determination 

 of the solar parallax the exposures were made following alternately the stars and 

 the planet. A comparison of the two series will not show the existence of a 

 systematic error constant for stars of all magnitudes, but it would show an 

 error which was a function of the magnitude. Forty exposures each of eighteen 

 selected stars have been measured, and show no trace of such an error. The 

 author concludes, from the absence of a differential effect between stars of 

 different magnitudes, that the absolute systematic error due to trail is probably 

 insensible. 



