H)'i DAVE>rPORT AOADExMY OF NATURAI, SCIENCES. 



Mr. Pratt made some remarks upon the subject of "a fourth dimen- 

 sion in space," so called, and gave extracts from published writings 

 by Prof. Zollner of Leipzig, Prof. Simon Newcomb, Mr. Halsted and 

 others. He explained the meaning of the "•three dimensions in 

 space" and showed the utter inconceivability of a fourth dimension. 

 He then proceeded to present a different hypothesis by which certain 

 physical phenomena, indicating the temporary suspension of the 

 property of impenetrability of solid bodies, might be accounted for, 

 and referred to several well known facts which seem to point toward 

 such a possibility. 



February -txH 1881 — Geological Section. 

 Prof. W. H. Barris in the chair. Three members present. 

 Prof. Barris presented a collection of sixteen species of fossils from 

 the coal measures of Elk Falls, Kansas. 



February 25th — Regular Meeting. 

 The President, Mr. J. D. Putnam, in the chair. Twelve members 

 and several visitors present. 



A resolution was adopted adding the following article to the By- 

 Laws: — 



Article XI. — Publications. 



Sectiox J. The regular publications of the Academy shall consist of Pro- 

 ceedings in octavo and the Memoirs in quarto. 



" The Proceedings shall contain such original papers, presented to the 

 Academy and accepted by the Publication Committee, as may be conven- 

 iently published in octavo torm, together with sncli extracts from the Rec- 

 ords of the Academy as the Publication Committee may consider of suffi- 

 cient interest to print. 



The Memoirs shall contain such papers as, on account of their size or il- 

 lustrations, can best ])e published in quarto form. 



Section II. The Publication Committee shall fix the jirice ujion the var- 

 ious publications of the Academy, at whicli they shall b(> sold to menil)ers 

 and the general public. 



Section III. There shall be established a permaueni publication fund, 

 the principal of which shall be inve.sted in safe, interest-bearing securities, 

 and the interest only, used. Any i)erson contributing not less than $.j0.00 

 to this fund sliall be entitled to all volumes of the Proceedings issued there- 

 after for life, and any person contributing not less than flOO.OO shall be en- 

 titled to all publications of the Academy issued thereafter for life. 



The following paper was presented: 



