106 
POPULAR SCIENCE REVIEW • 
but that a uniform climate extremely favourable for vegetation — but not 
on that account necessarily tropical — prevailed from the Equator to the 
Poles. 
MECHANICS. 
Browning' s Patent Self-acting Latch . — One of the best — because it is at 
once the most efficient and withal the simplest kind of bolt that we have for 
some time seen — is the ingenious invention of Mr. Browning, which is 
figured below, and which has been recently patented. But besides its sim- 
plicity, it has a special advantage, viz. that any attempt to open it from the 
outside renders it more securely fastened than it was before, while it registers 
the attempt made to open it by an alteration in its position. The bolt must 
be seen to be fully appreciated, and we doubt not it will soon become a most 
popular contrivance. It is certainly the most ingenious and yet the simplest 
invention in this direction that we have ever seen. 
A Machine for Darning Stockings . — We have had sewing and knitting 
machines for some time, but the latest addition to our stock is that of a 
darning machine, which is described by the u Scientific American ” as fol- 
lows : — il Two small plates, one stationary and the other movable, are placed 
one above the other. The plates are corrugated, and between them the 
i holy ’ portion of the stocking is laid. Twelve long-eyed pointed needles 
are arranged side by side in a frame, which last is carried forward so that 
the needles penetrate opposite edges of the hole, passing in the corrugations 
between the plates. Hinged just in front of the plates is an upright bar, 
and on this is a cross-piece carrying twelve knobs. The yarn is secured to 
an end knob, and then, with a bit of flat wire, pushed through the needle- 
eyes. Then the loop between each two needles is caught by the hand and 
hooked over the opposite knob, so that each needle carries really two threads. 
Now the needles are carried back to their first position, and, in so doing, 
they draw the threads, which slip off the knobs through the edges of the 
fabric. A little push forward again brings the sharp rear edges of the 
needle-eye against the threads, cutting all at once. This is repeated until 
the darn is finished, and beautifully finished it is. The cost of the machine 
is but ten dollars.” 
