€56 



SGIENGE. 



[N. S. Vol. IV. No. 96. 



iel Riordan, pastor of St. Elizabeth's parish, 

 Chicago, and Eev. Father Joseph F. Mooney, 

 Ticar-general of the diocese of New York, and 

 from these the Pope will select the rector, who 

 will probably be the first recomraendation of 

 the board. The board of directors decided that 

 the term of rector should be limited to six 

 years. 



The will of the late P. B. O'Brien, of New 

 Orleans who died a few days ago, leaves $150,- 

 000 to the Catholic University at Washington 

 to endow three chairs. 



DISCUSSION AND CORRESPONDENCE. 

 HALSTED ON THE STRAIGHT. 



Having returned from Eussia so recently as 

 not yet to be abreast of our current scientific 

 literature, it is to the courtesy of the editor of 

 Science that I owe my knowledge of the ap- 

 pearance in that journal of an important note 

 by Prof. Fiske, headed ' The Straight Line as 

 a Minimum Length.' 



This note is right in maintaining that for the 

 comparison of non-congruent lines, e. g,, the 

 straight and circle, an assumption in addition 

 to those of Euclid is essential. The strange 

 thing about it is that in stating what Prof. 

 Halsted ' appears to believe,' Prof. Fiske credits 

 me with ignorance of the very principle which 

 I of all the geometers have set forth most 

 strenuously. To attract particular attention to 

 it, I, in my Elementary Synthetic Geometry 

 put it in the following somewhat bizarre form : 



"In accordance with our definition of equiva- 

 lent magnitudes, as such as can be cut into 

 pieces congruent in pairs, no arc can be equiva- 

 lent to a sect [piece of a straight] . " 



For the sake of comparison we make the fol- 

 lowing assumptions : 



1. No arc is less than its chord. 



2. No minor arc is greater than the sum of 

 two tangents from the same point to its ex- 

 tremities. 



By these paradoxal assumptions we attribute 

 length to the curve, and can, e. g., evaluate the 

 circle in terms of its diameter to any desired 

 degree of approximation." 



George Bruce Halsted. 



THE curve-tracing TOP. 



Editor op Science : In your issue of Oc- 

 tober 9th, Mr. Warring refers to the very inter- 

 esting and instructive article by Prof. Barus on 

 the curve-tracing top or 'gyrograph,' which 

 article appeared in Science on September 25, 

 1896. Mr. Warring suggests as an improve- 

 ment in the apparatus that, instead of a lead 

 pencil and paper arrangement, a smoked glass 

 be used, the plate to be afterwards flowed with 

 thin varnish. I would suggest, as a further 

 modification, a very simple process which I 

 have found of great convenience and service in 

 a number of self-registering and tracing de- 

 vices. Long ago I discarded the use of 

 smoked glass in favor of glass plates coated 

 with a thin layer of printer's ink. The ink can 

 be applied with an ordinary hand-press roller, 

 and can be distributed with almost perfect uni- 

 formity. The plate so prepared should receive 

 the tracing while the ink is wet; then by ex- 

 posure to the air the ink dries and the record 

 is comparatively permanent. Such a plate 

 may be used as an ordinary photographic nega- 

 tive in making blue prints or silver paper 

 copies. Jas. E. Talmage. 



University of Utah, 



Salt Lake City, Utah. 



geology in the colleges op the united 



STATES. 



In the discussion and correspondence of Oc- 

 tober 2d, Mr. F. W. Simonds, of the University 

 of Texas, discusses Prof. T. C. Hopkins' report 

 on this subject. It seems to me that Prof. 

 Simonds treats altogether too severely those 

 smaller colleges which still give courses in his 

 judgment inadequate. It is scant justice to 

 class all those who do not furnish contributions 

 to geological literature as amateurs. It does 

 not follow that a teacher who is occupied with 

 details of administration to the exclusion of au- 

 thorship is not quite as good a teacher as 

 another who may contribute many papers. 



The contention that geology is a subject of 

 as great disciplinary value as the other sciences 

 no one will dispute. 



The situation in the smaller colleges is some- 

 thing like this : Many of them are unable to 

 develop all lines of scientific work in a disci- 



