NOVEMBER 19, 1897. ] 
THE BRITISH AND AMERICAN ASSOCIATIONS. 
To THE EDITOR OF SCIENCE: Those mem- 
bers of the American Association for the Ad- 
vancement of Science who went from Detroit 
to Toronto naturally made comparisons as to 
the methods by which the affairs of the two or- 
ganizations were conducted. Permit me, there- 
fore, as one who attended both meetings, to 
suggest three things which, if properly carried 
out, will tend to improve, at least to a certain 
extent, some features in the American Associa- 
tion. 
First. The addresses of the President and 
Vice-Presidents of sections should be in type 
and ready for publication at the time of the 
meeting of the Association, By this means the 
addresses would be available to the daily and 
scientific press, and every address would be 
given out at the same time. At Detroit the 
President’s address was not properly reported 
by any local newspaper, and of the Vice-Presi- 
dential addresses only that of Professor Mason 
was available in pamphlet form. 
Second. All papers passed by the sectional 
committee should go through the hands of a 
competent press secretary, specially hired for 
the purpose, preferably a scientific man, who 
should prepare suitable abstracts of the same 
for publication. These abstracts should be du- 
plicated by some convenient copying process and 
given to reporters as desired. 
By the combination of these two methods a 
proper and dignified presentation of the work 
of the Association would be given to the public, 
and by using the same for the proceedings the 
publication of the volume could be begun at 
once at the close of the meeting. For with the 
addresses in type and the abstracts in manuscript 
the volume could be put together and issued as 
soon as it could be printed. 
Third. In lieu of the single public reception 
_given on the first evening of the meeting I 
would advocate a greater number of social 
functions at which the members could meet 
each other. At each meeting of the British 
Association, besides a reception, there is always 
a conyersazione and a subscription dinner 
which is given in honor of the retiring Presi- 
dent. Would not such gatherings tend to bring 
the members of our Association into closer re- 
SCIENCE. 
775 
lationship with each other? For, after all, it is 
often the spoken word rather than the formal 
paper that suggests a line of research or is most 
fruitful in aiding workers in science. 
Marcus BENJAMIN. 
U.S. Nationa Museum, November 6, 1897. 
SCIENTIFIC LITERATURE. 
Boletin del Instituto Geologico de Mexico. Nums. 
7,8 y 9. El Mineral de Pachuca. 
Since the Geological Survey of Mexico was 
placed in charge of Sr. J. G. Aquilera, two or 
three years ago, the work has been prosecuted 
with great energy and several quarto bulletins, 
well illustrated, have been issued. These include 
a sketch of Mexican geology, studies of rocks 
and fossils as well as studies of special areas. 
The yolume named at the head of this note 
gives the results of detailed examination of a 
well-known region which, more than once, has 
attracted the attention of Kuropean geologists. 
There are chapters by nearly all members of 
the staff, illustrated with 8 large maps and dia- 
grams and 6 quarto plates. These describe 
elaborately the physiography, general geology, 
veins, and microscopic character of the rocks 
as well as matters of economic interest. 
The district of Pachuca, not far from Mexico, 
is almost midway in the Sierra de Real del 
Monte y Pachuca, on the lower half of the 
westerly slope and near the southwest border 
of the Sierra. It embraces about 20 square 
kilometers and its principal mines are in three 
ravines which unite to form the Rio de Pachuca. 
Its output of silver in former years was almost 
fabulous, but since 1895 it has been practically 
idle, owing to the flooding of the mines. Now, 
however, the drainage operations promise to be 
successful and the geological structure of the 
region becomes of much interest to Mexicans. 
The rocks are all eruptives, though sedi- 
mentary deposits, most probably Cretaceous, 
are shown within a short distance. Andesites, 
rhyolites and basalts are the forms, and of each 
there occur numerous varieties in texture, 
color aud composition. The chapter on the 
general geology by Aguilera and Ordofiez gives 
much detail respecting the macroscopic features 
of these rocks and their chronological relations. 
The authors feel justified in concluding that 
