36 = British Association for the Advancement of Science. 
timber frame. This was obviated by making the side of the 
vessel solid for twelve inches before and aft the bulk-head, and 
closing up the interstices with felt. As to the number of these 
compartments, he had found, after several trials, four bulk-heads, 
forming five sections, unexceptionable. The length of these sec- 
tions was arbitrary ; Mr. Williams made the centre one enclose 
the machinery, and those at the stem and stern of comparatively 
small length. He had, two days before, tried several experi- 
ments with the Royal Adelaide, having admitted the water by 
boring holes, first into the foremost section, next into the second, 
and afterwards into the third; and in each instance very little 
ion had been produced in the stem, never exceding twelve 
inches, while there was no disturbance to the men at work. In 
cases of fire, too, there was a double advantage from this arrange- 
ment; the fire could not extend far under deck, so that the men 
could work easily in extinguishing it,—there would be no cur- 
rent of air throughout, and the water might, if necessary, be ad- 
mitted to the section attacked by the fire, without any general 
inconvenience, and without any danger. Mr. Williams intimated, 
in conclusion, that a vessel would be placed by the Company at 
the disposal of members of the Association returning to Treland, 
as it had been to transport them to Liverpool.—The President 
then closed the meetings of the Section, by a few remarks on the 
successive developinert of power apparent in it. Though ori- 
ginally only an offset from another Section, it now rivalled, if it 
did not exceed any of the others, in the variety and interest of 
the topics discussed, the attendance of members, and the ability 
of the papers laid before it. He, as its original proposer, felt es- 
pecially interested in its progress, and a3 to see it still more 
distinguished. 
Heat of the Earth.—The sun’s heat was found to extend to vari- 
able depths at various places, and with many alternations of increase 
and diminution ; and it was in general necessary to descend from 
one to two hundred feet before the effect of this cause disappeared ; 
from thence downwards, the evidence of an increasing tempera- 
‘ture seemed to be quite satisfactory. At a colliery at Wigan, 
—_ the surface mean temperature was 50°, at 50 yards deep 
nperature was constantly 53°; at 150 yards deep the tem- 
as 56.75° 5 at 260 yards 63°. From this set of ob- 
it apy ut of 100 yards was accompa- 
