334 Chronicles of Science. | April, 
Ardsley machine is being used in several collieries, and the reports 
are in the highest degree satisfactory. 
In connection with this really important subject, a very admirable 
paper was read at the Institution of Civil Engineers, on February 16, 
by Mr. Thomas Sopwith, jun., on “The Actual State of the Works 
on the Mount Cenis Tunnel, and Description of the Machinery Em- 
ployed.” 
So much has been said of late respecting this extraordinary under- 
taking, and of the machinery employed in boring this tunnel, that we 
need not occupy our pages with any description of either the one or 
the other. The following brief quotation shows the present rate of 
progress :—* The tunnel, on 30th June, 1863, had been driven (includ- 
ing the advanced gallery), at Modane, 1092-25 metres, and at Bardon- 
neche, 1450°00 metres. The advancement in June last, at Modane, 
was at the rate of 4°719 feet per day. At this rate of progress at both 
ends, the tunnel would be finished in nine years two and a-half months 
from that time.” 
The machine employed by M. Sommeiller is very accurately 
described, and admirably-executed drawings are given in a work by M. 
Armengaud (ainé).* In the same work will be found a description of 
a rotating perforator, “ perforateur rotatif,’ of Schwartzkopf and Phil- 
lipson. This machine is exceedingly portable, and especially appli- 
cable to the conditions which prevail in our metalliferous mines. 
Attention has been directed, since the experiments which have been 
made at Mont Cenis, to the use of boring machinery in the metallifer- 
ous mines of this country. A machine, invented by Mr. Crease, but 
resembling strongly the machine just noticed, has been used in the 
Vigra and Clogau gold mine, near Dolgelly. The result of the trials 
made in driving a level, went to show that several improvements were 
- required ; consequently it was placed in the hands of Mr. Green, of 
Aberystwyth, and that gentleman has shown much mechanical in- 
genuity in adapting new principles to the original idea. The improved, 
or Green’s boring machine, is shown in the accompanying plate. This 
machine consists of (Figs. 1, 2) an upright pillar of cast-iron, 8, fixcd 
upon a low tram waggon, 1, running upon rails in the level, and having 
within it, in the upper part, an upright screw, 4, and cross-head ; and 
in the lower part another screw, 2, by means of which the machine 
can be firmly fixed between the floor and the roof. This pillar is 
encircled by an iron collar, 5, which can revolve round the pillar, but 
which can, by means of a rack and pinion, 7, 8, worked by the worm, 
6, be raised or lowered upon it. Attached to this collar is an arm 
with adjustments, 9, 10, 11, 14, which carries the boring machine 
proper (Fig. 4). At the end of the arm is a cylinder resting upon a 
screw bed (Fig. 3), 15, in which works an ordinary slide valve. The 
piston is shown in section in Fig. 4; to it is attached a hollow piston- 
rod, in which the borer is placed. By the side of the cylinder are 
* «Publication Industrielle des Machines, Outils et Appareils les plus perfec- 
tionnés et les plus récents, employés dans les différentes branches de l'industrie 
francaise et étrangére.’ Par Armengaud (ainé). Paris: MM. A. Morel et C'. 
See also ‘ Les Mondes, Reyue Hebdomadaire des Sciences,’ 21 Jan., 1864. 
