22 
in darkness when lie neitlier expects nor desires such a 
result ; and to get rid of tliis annoyance he would prop up 
the damper and effectually prevent its falling even when it 
was desirable that it should do so, i. e. when it happened to 
be in a fiery part of the mine. In other respects this lamp 
is much like the one invented by Upton and Roberts. The 
air for feeding the flame enters through holes beneath, and 
is brought into immediate contact with the wick by means 
of a brass cup. The sides of the lamp are partly glass and 
partly brass, fitted together so as to prevent the admission 
of air. In Upton's lamp there is a wire gauze cylinder 
inside the glass, but in Mr. Fletcher's there is none. By 
this omission the light produced is much stronger, but the 
safety is materially lessened ; for if the glass of Mr. F*s 
lamp were accidentally broken, the naked flame would be 
exposed to the fire-damp, and an explosion would ensue. 
Mr. Morton stated that he had submitted this new lamp to 
a variety of experiments both in and out of the coal mines, 
and he considered it deserving of the attention of this society . 
He thought the invention was still capable of considerable 
improvement, and hoped that Mr. Fletcher (though a gentle- 
man entirelyunconnected with miningpursuits) would devote 
more of his time and talents to the perfection of an apparatus 
the ingenuity of which had already entitled him to the thanks 
of the public. Mr. Morton remarked that the necessity of 
attempting to improve the safety lamp would become more 
generally manifest if it were universally known that Davy's 
lamp is not safe under certain circumstances. When " the 
Davy" is introduced into an imflammable atmosphere, at rest, 
it may be said to be safe ; but if the lamp be in motion, |or 
if a current of fire-damp be directed upon it, there is great 
danger of explosion. By means of a gas jet on the lecture 
table, Mr Morton caused the flame of " the Davy" to pass 
from the inside to the outside of the wire guage cage ; and 
he contended that, under similar circumstances, an explosion 
must inevitably ensue in a firey coal mine ; and he had no 
doubt some of the dreadful catastrophes that have occurred 
in the pits were occasioned in this manner. Mr. Morton 
said that the over zealous admirers of Davy had attributed 
a quality of infallible safety to an instrument which its illus- 
trious discoverer never ventured to claim for it. On the 
contrary, this distinguished philosopher, in a treatise which 
he published more than twenty years ago on the subject of 
the safety lamp, distinctly points out its unsafety when 
introduced into an inflammable atmosphere in rapid motion ; 
and he warns his readers against using " the Davy" under 
such circumstances. Mr. Morton was of opinion that if 
the notion which generally prevails about the absolute and 
certain safety of " the Davy" were dispelled, it would have 
