62 American Quarterly Microscopical Journal. 



together with Drs, Geo. E. Blackham, J. Edwards Smith 

 and \Vm. H. Atkinson, constitute for this year the committee on 

 publications. 



We wish the new society the best success, and trust that 

 the Buffalo meeting will show that there is sufficient enter- 

 prise and enthusiasm to ensure its future well-being. 



To return to the proceedings of the Congress we will give 

 a brief account of each day's programme. 



On Wednesday, Aug. 14th, the Congress assembled at the 

 court house soon after ten o'clock. Rev. A. B. Hervey, of 

 Troy, was made temporary chairman, and Mr. H. F. Atwood, 

 of Chicago, secretary. Proceedings were then opened by a 

 prayer, when Mayor Caven delivered an address of welcome 

 on behalf of the city, and Dr. Orpheus Evarts followed with a 

 similar one on the part of the scientists who had called the 

 meeting. Dr. Evarts's address was in every way appropriate to 

 the occasion. 



The chairman responded briefly, and a committee was at 

 once appointed to nominate permanent officers for the Con- 

 gress. The officers thus nominated and elected were : Dr. R. 

 H. Ward, president ; Prof. J. E. Smith, and Dr. W. W. Butter- 

 field, vice-presidents ; H. F. Atwood, Chicago, secretary ; and 

 Dr. J. B. Marvin, of Louisville, treasurer. 



The reading of papers began at once after this election. The 

 first one was read by the secretary, as the writer. Prof. W. A. 

 Rogers, was not at the meeting. The subject of Prof. Rogers's 

 paper was : 



" THE LIMIT OF ACCURACY IN MEASUREMENT WITH THE MICRO- 

 SCOPE." 



This paper was quite elaborate, and embraced the results of 

 experiments in measuring minute spaces in tabular form. For 

 the most part the figures of Prof. Morley were compared with 

 those obtained by the author, both measuring the same lines 

 independently. 



The results are summed up by Prof. Rogers, as follows : 

 "I. Two equally skillful observers can measure the same space within 

 about one-300, 000th of an inch if the space does not exceed one- 500th 

 of an inch. For a space of one- 1 00th of an inch, the deviation will 

 probably amount to one-8o,oooth of an inch in case the measurements 

 are made with an eye-piece or a filar micrometer. 

 2, The average deviation for accumulated errors, under similar condi- 



I 



