IATI"NS FOK ADVAXCEMEXT "F SCIEXCE. ( AMKRU.-A.V.) 



31 



10 A.M.. Aug. ~4. The in railed to order 



! IwardW. Morley. the retiring president, who 



introduced the new preMdeiit. Edward Drinker 



. wlici then took charge of the meeting, tin- 6X- 



wliich began with prayer by the Rev. Dr. 



Charles H. F.>wkr. Methodist Episcopal Bishop of 



EDWARD D. COPE. 



Buffalo. Mayor Edgar B. Jewett. chairman of the 

 local committee, was introduced and welcomed the 

 scientists to Buffalo, extending to them the freedom 

 of the city and calling attention to the various 

 point? of interest in and about Buffalo. Dr. ];<> 

 well Park then delivered an address of welcome in 

 behalf of the Buffalo. Society of Xatural Sc; 

 in which he said: " Xot the least of our pleasint 

 recollections in seeing you now is the remembrance 

 that after the period of your inactivity during the 

 civil war your first meeting for reorganization was 

 held in Buffalo. Twice since then your association 

 has honored us by selecting Buffalo as a meeting 

 place, and now we again extend to you a welcome 

 bounded only by the city's limits and the hospital- 

 ity of its citizens." lie spoke of the Buffalo Society 

 of Xatural Sciences, outlining its work in the pro- 

 motion and study of natural - nd calling 

 particular attention to its working library and the 

 museum with its valuable collections. "President 

 Cope responded to this address, and spoke of 

 original research as promoting mainly the ad- 

 vancement of science, saying: "Love of research 

 makes a man devote himself to the study of sci- 

 ence, and it means endless advantages both to the 

 investigator and to those who profit by his research. 

 The scientific career is one which offers great ad- 

 vantages in this country, rich in the elements that 

 make the calling a source of delight. It is a life of 

 happiness, for in congenial labor is found happi- 

 ness. In the line of intellectual progress the scien- 

 tific career offers the very best." Permanent 

 retary Putnam announced the names of 11 members 

 of t ion who had died during the year, 

 including 3 founders of the association (Ti 

 T. Bonve. Bela Hubbard. and Josiah D. Whitney) 

 and a past {(resident (Prof. Hubert A. Newton, of 

 Xew Haven. Conn). 



Address of the Retiring President. The as-- 



.-ociatiou met in the chapel of the High School at 

 s 1-. M.. Aug. '24. to hear the retiring address of Ed- 

 ward \V. Morley, who during the past ten years lias 

 devoted his leisure to study of the atomic weight 

 of oxygen, a research that has gained for him the 

 reputation of having finally settled that question 

 upon which the atomic values of all the other ele- 

 ments so largely depend. The title of his address 

 was A Complete Chapter in the History of the 

 Atomic Theory.'' He said: "The history of the 

 atomic theory for ninety years would fall into sev- 

 eral distinct chapters. One of these would tell of a 

 large amount of work, some of it of consummate 

 accuracy, of which the object was to attain some 

 knowledge of the nature or construction of atoms. 

 Since the last meeting of our association in this 

 city work has been accomplished which, if I rightly 

 judge. has ended this particular chapter. Dalton's 

 theory was founded on three facts. One of these is 

 the law of definite proportions: in any chemical 

 compound the ratio of the components is constant, 

 is invariable, is definite. A second of these laws of 

 Dalton is the law of equivalent proportions : if two 

 elements which combine with each other combine 



with a third, then the ratio in which they com- 

 bine with each other (or a simple multiple of it) is 

 also the ratio of the quantities of those which com- 

 bine with the same quantity of the third. The 

 third law is the law of multiple proportions : if two 

 bodies combine in more than one ratio, those ratios 

 are simple multiples of each other. These three 

 laws are statements of facts. Careful and multi- 

 plied experiments have convinced us that, if these 

 statements are not rigorously exact, their deviation 

 from accuracy is less than the accidental errors of 

 the best experiments used to test them. The deter- 

 mination of atomic weights is the chemical process 

 in which the highest degree of precision is demand- 

 ed. If we denote the precision of such determina- 

 tion by the words 'good.' ' excellent.' 'admirable.' 

 consummate.' then we may say that in a good 

 series of determinations the average difference from 

 the mean of all will be less than one-one-thou- 

 sandth part of the ratio sought : in an excellent 

 - than one-three-thousandth part: in an 

 admirable - than one-ten-thousandth part : 



and in a consummate series, less than one-fifty- 

 thousandth part. Dalton inferred that chemical 

 elements consist of very small units or individuals: 

 that all the units or individuals of any given ele- 

 ment are equal in weight ; and that combination 

 takes place by the grouping together of different 

 units or individuals. This is Dalton's atomic theory. 

 In Dalton's time there was no fact opposed to this 

 novel conclusion: but there was no second set of 

 facts to support it. A few years after Dalton had 

 formed the atomic theory. 'and had obtained the 

 first experimental evidence on a matter which had 

 enlisted attention for more than two thousand 



-. Davy showed that certain bodies were com- 

 pounds, although they had resisted all previous at- 

 tempts to decompose them. Trusting to experi- 

 ments of not much accuracy. Pro d in 

 I*!.") that probably the atomic weights of other 

 elements were divisible, without remainder, by the 

 atomic weights of hydrogen : or. in other words, 

 that they are whole numbers, if the atomic weight 

 of hydrogen be taken as unity. Dumas, than whom 

 none in France stood higher, whose opinion had 

 great weight on account of the excellence of his 

 many determinations of atomic weights, accepted 

 Front's hypothesis with a slight modification, and 

 believed that his experiments had established its 

 truth. Stas. the distinguished pupil of Dumas, be- 

 gan his work with a bias in favor of the hypothe- 

 ut when his first series of admirable deter- 



