242 
On the Excavation of tallies. 
[Aug. 
wishes of the public, whom it is meant to benefit, it must succeed. There 
is no want in Calcutta of means or of talent to apply them, nor would there be of 
funds if they were required — 1 mean, supposing people generally desirous of 
seeing the thing succeed. But if we allow ourselves, as happens to most of our 
Indian projects, to be talked into apathy and indifference, of which we have, surely 
a sufficient quantity already, the usual result will of course follow, — of disgust 
in those who had undertaken the conduct of the matter, and the consequent 
abandonment of the undertaking. That this may not be the case, I think 
most of your readers will join with me in most heartily wishing, as well for 
our own sakes, as in justice to those public-spirited individuals to whose ex- 
ertions we owe, that the experiment has been attempted at all. To them 
the public are at all events much indebted : if they succeed, they may reckon 
with certainty on the gratitude of their fellow citizens ; while even if they fail, they 
will at least be allowed tbe credit of having engaged in an undertaking which 
had every rational prospect of success, requiring but a small expenditure of means 
for its prosecution, yet calculated, in the event of being successful, eminently to 
benefit tbe public. But to my hypothetical “ if they fail they might perhaps 
well reply in the words of Lady Macbeth, 
(( But screw your courage to the sticking point. 
And we’ll not fail.” 
It is certain, that to anticipate failure, and to urge ill considered and frivolous 
objections, is the way to insure the event professed to be deprecated; while a 
confiding and generous spirit of encouragement and sympathy, must, on the 
contrary, command success, if it be possible. 
C. J. 
III . — On the Excavation of Vallies, as illustrated hy the Volcanic 
Rocks of Central France. By Charles Lyell, and R. I. Murchi- 
son, Esqs. 
[From the Scotsman Newspaper. J 
This is a curious paper, and throws considerable light on some scientific ques- 
tions which have been the subject of much speculation. It has, however, one 
material fault. Partly from the intricacy of the matters discussed, and the want 
of a sufficient number of illustrative drawings, and partly from the inattention of 
the writers, it is greatly deficient in clearness. This must have been, we think, in 
part the consequence of inattention, for Mr. Lyell’s excellent paper on the Geolo- 
gy of Forfarshire, shews that he can write with great perspicuity on such subjects. 
The present paper is long, and were we to attempt to follow the authors into their 
details, we would soon leave our readers behind us. We shall, therefore, confine 
ourselves to a general view of the conclusions to which the facts seem to lead, so 
far as we can comprehend them. 
There are two opinions respecting the excavation of vallies. One regards 
them as produced by the erosive action of the streams which we now see 
flowing in them, continued through a long lapse of ages, and aided by rains, frost, 
and heat; the other attributes them to the agency of a temporary deluge sweep- 
ing over the surface with powerful currents. The first opinion is that which would 
niost readily occur to any observer; and the second has been resorted to. chiefly 
to escape from tbe difficulty arising from the prodigious length of time which ap- 
pears to be necessary, to enable a cause operating so slowly, to work such mighty 
changes. There are two strong reasons, however, which militate against the sup- 
position, that diluvial currents have hollowed out vallies, at least the vallies iniuoun- 
tainous districts. First, these vallies are generally shut at their upper extremities, 
winch they would not have been had they owed their existence to diluvial currents; 
and secondly, the vallies in each district, generally speaking, bear a certain propor- 
tion in magnitude to the streams flowing in them. Thus the valley of the main 
tuink of the stream is always larger than that of its primary branches, and the 
v.t ie.«, of the primary branches are larger than those of the secondary. The di- 
rbrhi° n tf i° ,^ lese branches, which always forms a considerable angle, often a 
erf • e> ^*at of the main stream, is not easily reconciled with the suppos- 
a D ency of a deluge. Thus a series Qf the great waves, or an oceanic current. 
