New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1860-08-08

Vile. Mr. Puch. in connection with Mess's. Laws
and Gilbert bad made large series Of costly and care
fu experiments which no described and Illustrated ny
diagrams confirming Boussngaults results. Legumn-
ants they did not succeed WITH neither coVtr'
beais nor peas. Messfs. Laws and Gilbert are con,
nuing the investigations with regard TO that ootanc
family Mr.. Pugh added come remarks On e9lI. ,n
results Of his investigations confirming the doctrine
that plants do not develop free nrogeh rom
position of their heterogeneous compounds, &C :.
After a brief conversation on the agricultural III
portaDce of the subject, the section aalou[neu'
SECTION OF NATURAL HiSIohf' :
Col. Id. Graham, L. s. A., gave an account Oh
careful experiments and measurements In the grea'
lakes of North America, by when IL mas oeeh ucno
streted that tidal are to DO fOuhd there auo
mo at their greatest hight 10 about four and hi
Prof Whitney remarked upon the great interest OF
communication which has settled question 30 long
Mr.. f. B. Elliott of Boston gave the results OF his
;nyestigation into the rate Of mortality among the
blind showing that, upon the whole the vlaity OF the
blind does not equal either from congental weakness
of constitution, or from their raouty 70 tahe
exercise Yd care Of their health the vitality OF other
persons. - - .,uua
Abon one person in 900 or in 25OO Is blind Is ths
necessary Dr. Howe doubts whether il is but believes
that with more steadfast obedience TO physical law,
blindness will become more rare, and finally cease.
Those who are born with sight and afterward become
blind from slight causes, he thinks had lack OF vital
tied Of sourse he does not speak OF those who lose
eight by vioerce, such az blasting rocks Blindness
from such cannot epropagaedi the offspring:
The doctor once found robin born blind, buth did
not suppose it grew to maturity and Matched blind
Young In closing he ntimeed, in gentle way, thai
while we show the greatest kindness and consideration
to the blind, we ought to discourage the marriage OF
the weak the scrofuous, blood relations aud persons
both of whom of the feebler tempera ments, aud
those who were born nearly or quite blind.
Mr.. W. w. Wheildon read paper on the open
Polar Sea.
Mr.. c. Ii. Hitchcock read an article upon the origin
of Taconic rocks in Vermont.
DR.. NewbeIry also read paper upon the extinct
Flora of North America.
Lieut. O. A. Gilmore L. s. A., read some observa-
tons on hydraulic cements, enbodying the results OF
his reading and also of his experiments. lie spoke OF
the chemical questons first, concerning the compost
ton of the stone and then Of the changes that take
place in the setting Of the mortar 1t was once thought
that hydraulic lime must contain clay so az to form
double filicate of lime aud alumina; but it ID now
known that magnesa may replace the aumina, and 1t
may be that the presence Of other bases affects the
results But the straDgest result OF his experiments
was 10 be found in the fact that the hydraulic property
of lime produced from stone depends upon the length
of time that il was subjected to red heat Insufficient
burning will not produce the effect; extra burning will
also destroy it, But greater amount of burning will
restore it, and still greater degree again destroy 1t.
So that ia 10 have the stone burned to the
right degree. Various veins of stone in the same
onsrr vary in the amount of burning they require,
and there usually OF underburned ana over
burned stone in all ordinary hydraulic cemens. Lieut..
Gilmore thought the manufacturers would be repaid
they would separate the veins and burn the stone in
separate klns. The quckness of setting depends in
large degree also the temperature OF the water with
which the cement is mixed. The adhesiveness of the
mortar to stone is increased by mixing it thin the
strength and sOlidity by mixing il thick. Such are
some of the topics touched upon in this paper upon
practical and important matter.
The Association adjourned until Tuesday morning,
having accepted an invitation to take tea with DR..
S. G. Howe this evening at Lawions Valley, five
miles north Of Newport.