SCIENCE 
EDITORIAL ComMitrEEe: S. NEwcomB, Mathematics; R. S. WooDWARD, Mechanics; E. C. PICKERING, 
Astronomy; T. C. MENDENHALL, Physics; R. H. THURSTON, Engineering; IRA REMSEN, Chemistry ; 
J. LE Conte, Geology; W. M. Davis, Physiography; O. C. MArsu, Paleontology; W. K. Brooks, 
C. Hart Merriam, Zoology; S. H. ScuppER, Entomology; C. E. Bressny, N. L. BRirton, 
Botany; Henry F. OsBorn, General Biology; C. S. Minor, Embryology, Histology; 
H. P. BowpitcH, Physiology; J. S. Brnuineas, Hygiene; J. McKEEN CATTELL, 
Psychology; DANIEL G. BRINTON, J. W. POWELL, Anthropology. 
Fripay, OctoBer 1, 1897. 
CONTENTS: 
An Undiscovered Gas: WILLIAM RAMSAY......... 493 
Address by the President before the Society for the 
Promotion of Engineering Education: HENRY T. 
Anthropology at the American Association for the 
Advancement of Science: ANITA NEWCOMB 
IMIG CAST eonneacanonooocasasnHoHonteasecosececG9900090602000000 508 
Columbia University Zoological Expedition of 1897 : 
(GAG ING CQUNTEICEIS Shasceonceannocdoecasoccaonsqn0oscoQdcd 513, 
Mimicry in Butterflies of the Genus Hypolimnas and 
its Bearing on Older and more Recent Theories of 
Mimicry : EH. B. POULTON.........0ccseseeeeeeeseneeees 516 
Notes on Engineering: R. H. T.........eesceseeeeeeeeee 518 
Scientific Notes and News ...........s0esesesenvecreeererenee 519 
University and Educational News :— 
Institutions for Higher Education in the United 
ISURLES) MN GENET Olseslecaneratconceeecececenetaecccsec enacts se 522 
Discussion and Correspondence :— 
Meteorology in South America: R. DEC. WARD..523 
Scientific Literature :-— 
Navaho Legends: ALice C. FLETCHER. Botany 
Offi CPAZONes)..acnorecasterenccsereotecarerseicesoncere sect 525 
New Books. 
MSS. intended for publication and books, etc., intended 
for review should be sent to the responsible editor, Prof. J. 
McKeen Cattell, Garrison-on-Hudson, N. Y. 
AN UNDISCOVERED GAS.* 
A SECTIONAL address to members of the 
British Association falls under one of three 
heads. It may be historical, or actual, or 
* Address to the Chemical Section, British Associ- 
ation for the Advancement of Science, Toronto, 1897, 
by the President of the Section. 
prophetic; it may refer to the past, the 
present or the future. In many cases, in- 
deed in all, this classification overlaps. 
Your former presidents have given some- 
times a historical introduction, followed by 
an account of the actual state of some 
branch of our science, and, though rarely, 
concluding with prophetic remarks. To 
those who have an affection for the past, 
the historical side appeals forcibly ; to the 
practical man, and to the investigator en- 
gaged in research, the actual, perhaps, pre- 
sents more charm; while to the general 
public, to whom novelty is often more of 
an attraction than truth, the prophetic as- 
pect excites most interest. In this address 
I must endeavor to tickle all palates ; and 
perhaps I may be excused if I take this 
opportunity of indulging in the dangerous 
luxury of prophecy, a luxury which the 
managers of scientific journals do not often 
permit their readers to taste. 
The subject of my remarks to-day is a 
new gas. I shall describe to you later its 
curious properties ; but it would be unfair 
not to put you at once in possession of the 
knowledge of its most remarkable property 
—it has not yet been discovered. As it is 
still unborn, it has not yet been named. 
The naming of a new element is no easy 
matter. For there are only twenty-six let- 
ters in our alphabet, and there are already 
over seventy elements. To select a name 
expressible by a symbol which has not al- 
