C. Lyell on Fossil Reptilian Remains, etc. 33 
quent co-operation of action, than when separated and individ- 
ualized as they otherwise are. 
Parabolic reflectors and recesses of other forms in rear of the 
orchestra can be productive only of injury to the general effect, for 
inasmuch as all upon the stage cannot be in the focus, the greater 
asperities at first noticed. How this results it is perhaps not 
easy to explain. Can it be that from the constant vibration im- 
parted by the sonorous impulses to the solid materials some change 
is gradually induced in the arrangement of their integral mole- 
cules, after the manner in which agitation sometimes affects the 
intimate structure of crystallizable bodies? But doubtless much 
is to be attributed to the natural effect of time in drying and con< 
solidating and thoroughly assimilating the structure in all its 
various parts. 
We here conclude our imperfect essay, ending as we began, 
With the regret that architects and scientific men have not hon- 
ored with a more careful attention a subject so full of interest and 
SO intimately connected with the welfare of an Art, now almost 
Universally known and appreciated. 
“a 
Arr. IV.— On. the discovery of some Fossil Reptilian Remains, 
and a Land-shell in the interior of an erect fossil-tree in the 
Coal measures of Nova Scotia, with remarks on the Origin 9 
Coal-fields, and the time required for their formation ; by Sir 
C. Lett, F.R.S., V.P.G.S., &c.* 
Tne entire thickness of the carboniferous strata, exhibited in 
one uninterrupted section on the shores of the Bay of Fundy, in 
Nova Scotia, at a place called the South Joggins and its neigh- 
hood, was ascertained by Mr. Logan, to be 14,570 feet. ‘The 
® From Proe. Royal Soc. of Great Britain, March 18, 1853. 
Srcoyp Serres, Vol. XVI, No. 46,—July, 1853. 5 
