704 



SCIENCE. 



[N. S. Vol. V. No. 122. 



A paper on ' Experiments with X-Rays on 

 the Blind ' was read by Dr. H. L. Hilgartner, 

 oculist to the State Institution for the Blind. 

 This contribution is the joint production of Dr. 

 Hilgartner and Professor E. F. Northrup, of 

 the chair of physics in the University. As the 

 authors state, the experiments were stimulated 

 by the extraordinary claims made by Dr. Louis 

 Bell in a letter to the editor of the Electric 

 World (December 12, 1896), in which it was 

 maintained that a man totally blind from 

 paralysis of the optic nerve was able to dis- 

 tinguish the flickering of a Crook's tube. This 

 the authors wished to verify or disprove. As 

 to their apparatus they say : " The outfit em- 

 ployed in our test is of the best. A double 

 focus tube is excited by a Tesla coil capable 

 of giving an eight-inch discharge. The X-Rays 

 produced will show a shadow of the hand upon 

 the fluorescent screen at a distance of twenty- 

 five or thirty feet." Of the eleven persons 

 experimented upon, seven had no light percep- 

 tion ; they were sufiering from atrophy of the 

 optic nerve. Of the four having some light 

 perception, three were blind from affections of 

 the cornea and lens, and one from atrophy of 

 the optic nerve. After describing their experi- 

 ments the authors give as their conclusion 

 ' ' that the X-Rays themselves have no power 

 whatever of exciting vision or even light per- 

 ception in any kind of an eye, diseased or 

 normal. Of course, these results regarding the 

 blind apply only to the eleven subjects experi- 

 mented upon, and it would be unscientific to 

 say that no subject can ever be found in whom 

 the X-Rays will excite light sensations. None 

 of the blind subjects could see anything by 

 looking into the fluoroscope, even those having 

 some light perception getting no sensation, and 

 our experiments gave us no hint that the X- 

 Rays, or any other kind of rays, proceeding 

 from the Crook's tube are able to give any light 

 perception to those who are totally blind from 

 any cause whatever. "******* 



"We should not have thought the above 

 negative results worthy of record if the matter 

 had not been taken up by scientists of eminence 

 and the newspapers filled with trashy and mis- 

 leading myths. ' ' 



Mr. J. R. Bailey gave an account of his in- 



vestigations of the Hydrazine Derivatives of 

 Propionic Acid, being a continuation of his 

 studies begun more than a year ago in the 

 laboi-atory of Professor Thiele at Munich. 



A paper by Mr. M. B. Porter, now of Harvard 

 University, ' On the Roots of Bessel's Func- 

 tions,' was announced by title. 



Frederic W. Simonds. 



University of Texas. 



the academy of science of st. louis. 



At the meeting of the Academy of Science of 

 St. Louis, held on the 19th of April, 1897, 

 twenty-one persons present. Dr. C. Barck de- 

 livered an address on Helmholtz — his life and 

 work; and Dr. C. R. Keyes, the State Geologist 

 of Missouri, presented papers on the relations 

 of the Devonian and Carboniferous systems of 

 the upper Mississippi basin and the distribution 

 of Missouri coals. 



William Trelease, 



Secretary. 



NEW BOOKS. 



The Ancient Volcanoes of Great Britain. Sib 



Archibald Geikie. London and New York, 



the Macmillan Co. 1897. Vol. I., pp. xxiv 



+477, Vol. n., pp. xv+492. $11.25. 



The Theory of Electricity and Magnetism. Ar- 

 thur Gordon Webster. London and New 

 York, the Macmillan Co. Pp. x+576. $350. 



Elements of Astronomy. Sir Robert Stawell 

 Ball. London, New York and Bombay, 

 Longmans, Green & Co. 1896. Pp. xvi+ 

 469. 



Numerical Problems in Plane Geometry with Metric 

 and Logarithmic Tables. J. C. Estell. New 

 York, London and Bombay, Longmans, Green 

 &Co. 1897. Pp. vii+144. 



Topics and References in American History, with 

 Numerous Search Questions. George A. Wil- 

 liams. Syracuse, N. Y., C. W. Bardeen. 

 1897. Pp. viii+176. $1.00. 



EERATA: P. 591, col. 1, line 42 and col. 2, lines 

 14 and 29 for Puppis read f Puppis. P. 592, col. 2, 

 line 36 for March 19th read March 26th. 



