SCIENCE. 
123 
Resolved, That the Association feel and would hereby express 
the great loss which this service has suffered in the recent death of 
its chief officer, General A. J. Myer, whose energetic administra- 
tion of novel duties, seconded by his able corps of scientific 
assistants, has comm inded universal respect at home and abroad. 
Professor N. P. Lupton, of Vanderbilt University, was 
added to the committee on the best methods of scientific 
teaching in the public schools. The following were chosen 
a committee on the registration of deaths, births and mar- 
riages : E. B. Elliott, F. B. Hough, J. B. Kellebrew, 
Joseph S. Copes and E. T. Cox. 
It was voted yesterday to accept the invitation from 
Montreal for the meeting of the Association in 1882. 
CONCLUSION. 
The sections had all adjourned in the afternoon. In the 
evening a general session was held in Huntington Hall, 
President L. H. Morgan in the chair. About 250 ladies and 
gentlemen were present. A committee was appointed to 
confer with the President of the United States on the ap- 
pointment of a chief signal officer. The committee includes 
Professors Brush and Barker, Dr. Bell, President Gilman, 
Professor Harkness, Mr. L. H. Morgan, Professor Clarke 
and Mr. A. Hall. The Association voted its thanks to those 
who had helped toward making the re-union of 1880 so 
pleasantly successful. The respective resolutions were 
supported bv remarks from Professor Harkness, Judge 
Henderson, Professor Nason, the Rev. Mr. Shackelford, 
Professor Lattimore, Dr. J. Lawrence Smith, the Messrs. 
Hoveyand Procter, and from the chair. The American As- 
sociation for the Advancement of Science was then pro- 
nounced adjourned, to meet again, for the thirtieth time, at 
Cincinnati, on the 17th of August, 1881. 
We continue the publication of the addresses, and offer 
this week that by Dr. Asaph Hall, of Washington, and the 
Eulogy, by Professor A. M. Mayer, on the late Pro- 
fessor Joseph Henry, both of which we present in full ; 
also abstracts from the following papers prepared 
by the authors : — The Photophone, by A. G. Bell ; 
Mounds of Illinois, by William McAdams ; Determination 
of the Comparative Dimensions of Ultimate Molecules, by 
W. N. Norton ; Plan of the Cerebro-Spinal Nervous System, 
S. V. Clevenger ; Observations of the Planetary Nebulae, by 
E. C. Pickering ; Co-efficients of Gas Solutions (Cut) 
by E. L. Nichols and A. W. Wheeler ; The Wyan- 
dottes, by J. W. Powell ; Ancient Agricultural Imple- 
ments of Stone, by William McAdams ; The Endo-Cranium 
and Maxillary Suspensorium of the Bee, by George Mac- 
loskie ; Further Notes on the Pollination of Yucca, and on 
Pronuba and Prodoxus, by C. V. Riley ; Simple Device for 
Projecting the Vibration of Liquid Films without a Lens, 
by H. S. Carhart ; On Land Snails of the Palaeozoic Period, 
byj. W. Dawson ; The Structure of Mica Veins in North 
Carolina, by W. C. Kerr ; Transformation of Planorbis, by 
A. Hyatt ; The Languages of the Iroquois, by Mrs. E. A. 
Smith. 
ADDRESS BY PROFESSOR ASAPH HALL. 
Fellow-Members of the Association : — 
Astronomy, in some of its forms, reaches back to the 
most distant historical epochs, and the changes that it has 
undergone during this long lapse of time give to this 
science a peculiar interest. In no other branch of human 
knowledge have we such a long and continuous history of 
the search after truth, of the painful struggle through which 
men have passed in freeing themselves from theories ap- 
proved by the wise of their own times, and in overthrowing 
beliefs which had become incorporated into the life and 
culture of those times. Perhaps the grand array of the 
heavens, and the vast phenomena which they display, nat- 
urally led men to the invention of complicated theories ; 
but these passed away at last before the test of observation, 
and the criticism of sceptical men ; and the Copernican 
theory of our solar system, Kepler’s laws of elliptical mo- 
tion, and the Newtonian law of gravitation, gave to Astron- 
omy a real scientific character. 
The discovery of the laws that govern the motions of the 
heavenly bodies, and the construction of the theory of these 
motions, demanded from practical Astronomy better ob- 
servations and a more accurate determination of the 
orbits of the planets and the moon, or of the constants that 
enter into the problems of celestial mechanics ; and this 
demand led to an improvement in the instruments, and in 
the art of observing. The astronomers and instrument- 
makers of England and France led the way in these im- 
provements. The great national observatories of those 
countries were established, and in England Flamsteed and 
Sharp, Bird and Bradley, were foremost in raising practical 
Astronomy to the condition of satisfying the demands of 
theory. But theoretical Astronomy was soon to receive a 
wonderful advancement. Perhaps no one contributed 
more powerfully to this progress than Lagrange. The 
writings of this man were models of simplicity and elegance, 
and yet so complete and general are his investigations 
that they contain the fundamental theorems of celestial 
mechanics. By the invention and perfection of the method 
of the variation of the arbitrary constants of a problem, and 
by the establishment of the differential equations of a 
planetary orbit depending on the partial differential coeffi- 
cients of a single function, Lagrange reduced the question 
of perturbations to its simplest form, and gave the means 
of deducing easily the most interesting conclusions on the 
past and future condition of our solar system. To supple- 
ment this great theorist there was needed another kind of 
genius. Combining the highest mathematical skill with 
unequalled sagacity and common sense in its application, 
Laplace gathered up and presented in a complete and prac- 
tical form the whole theory of celestial mechanics. Be- 
sides his numerous and brilliant discoveries in theoretical 
Astronomy, Laplace gave us some of the finest chapters 
ever written on the theory of attraction,* and a complete 
treatise on the calculus of probability. 
By such labors as these the questions of Astronomy were 
brought into order and classified, and the attention of As- 
tronomers was directed better than ever before to the de- 
termination of the quantities which must be found from 
observation. Moreover, the refinement of analysis and the 
completion of theory brought out new and more delicate 
questions, not less interesting, and requiring more com- 
plete investigation and more powerful instruments. The 
careful examination and study of the instruments and 
methods of observation became necessary, as well as com- 
plete and rigorous methods of reduction ; and finally there 
was needed a critical and satisfactory method for the dis- 
cussion of observations. For these last improvements in 
Astronomy we are indebted chiefly to the astronomers and 
mechanics of Germany. 
Among those who contributed by means of their optical 
and mechanical skill to furnish Astronomy with the instru- 
ments necessary for its further advancement, no one holds 
a more honorable place than Joseph Frauenhofer. This 
man began his scientific work at the age of twenty-two, and 
died at thirty-nine, and yet in those seventeen years he 
gave to Astronomy great improvements in the manufacture 
of optical glass, driving clocks for equatorials, and tel- 
escopes and micrometers, that in the hands of Bessel and 
Struve gave to observations a degree of accuracy hardly 
thought of before. To such men as Frauenhofer and his 
co-workers, who have carried on and improved the con- 
struction of instruments of precision, practical Astronomy 
owes much ; and yet, after all, the principal thing in a 
science is the man himself. No matter how excellent the 
instruments may be, the question whether they shall be 
used for the advancement of the science, and shall con- 
tribute the full value of their peculiarities to help towards 
increasing the accuracy of astronomical determinations. 
* “ Ein schiines Document der feinsten analytischen Kunst,”— Gauss 
