1880.] 



MICROSCOPICAL JOURNAL. 



165 



focal length of the objective by 

 which it is formed. Prof. Tuttle 

 also objected to the conclusions of 

 the author and insisted that the in- 

 vestigator in biology must do the 

 whole work himself and could not 

 successfully leave any part of it to 

 othere. He thought that one who 

 coniined his microscopical studies to 

 a ^ objective would not accomplish 

 much. 



C. M. Yorce of Cleveland, Ohio, 

 read the next paper [see page 170], 

 entitled " Penetration in Object- 

 ives, is it a Defect or an Advan- 

 tage ? " The writer discussed the 

 images foniied by objectives of 

 the classes which he denominated 

 as " penetrating," and " non-pene- 

 trating '' or defining lenses, and the 

 deductions to be drawn there- 

 from. The conclusion reached was 

 that different kinds of objectives 

 were needed for different kinds of 

 work, and that both penetrating 

 glasses and defining glasses were 

 needed, each for its own class of 

 work. He thought if a micros- 

 copist could not afford to buy both 

 classes the lower power defining and 

 higher power penetrating objectives 

 were the most generally serviceable, 

 neither kind alone being sufficient 

 for all kind of work. There was 

 no discussion upon the subject of 

 this paper. Ten more new mem- 

 bers were admitted. 



In the evening many of the 

 members and a number of citizens 

 enjoyed a very pleasurable excursion 

 on the steamer Grace McMillan to 

 Wyandotte, and back. About 150 

 persons were on board. 



SECOND DAY. 



After the reading of the minutes, 

 etc., the Executive Committee re- 

 ported the following as approved 

 applicants for membership : The 

 Rev. William D'Orville Doty, Rosa 

 M. Redding, Chas. Shepard, M. D., 



W. B. Sprague, M. D., Allen Y. 

 Moore, W. G. White, Wm. A. 

 Clapp, John Sloane, Richard H. 

 Mohr, Albert McCalla. The gen- 

 tlemen named were elected mem- 

 bers of the Society. 



An invitation to the Society to 

 visit the Detroit Scientific Associa- 

 tion's Museum at Harper Hospital 

 in the afternoon, was accepted. 



Mr. C. M. Yorce read the first pa- 

 per of the day, which was entitled 

 " The Microscopic Examination of 

 Writing for the Detection of For- 

 gery, etc." 



I'he speaker treated the subject 

 at length, saying that he had a 

 great deal of interest in the matter, 

 and directed his attention both to 

 the verification of signatures and to 

 general writing. He was free to 

 say that he was as yet by no means 

 satisfied with the results which had 

 been attained, and thought that 

 many valuable additions might be 

 made to this branch of- practical 

 microscopy. He had considered 

 first, the general characteristics of 

 writing ; second, special character- 

 istics, modifications of or departures 

 from general characteristics. There 

 were five elements which deter- 

 mined the character of a person's 

 hand-writing: the paper, the pen, 

 the ink, the personal qualifications 

 of the writer, and the conditions 

 under which the writing was done. 

 Any one of these being changed 

 from the ordinary conditions, the 

 microscopic conditions of the writ- 

 ing were almost sure to be changed 

 also. So far as the paper is con- 

 cerned its surface is the only charac- 

 teristic which affects writing. The 

 harder and smoother the surface 

 the better defined is the writing 

 upon it, and the better chance there 

 is of determining any erasure, 

 change or interpolation. On paper 

 of good quality, with a good 

 pen and readily flowing ink, the 



