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MESSES. SCHNEIDER AND CO.’S WORKS.
a barrier to the proper flow of the metal, blow-holes
frequently appeared, causing a somewhat large proportion
of guns to be rejected.
This resulted in means being taken, a little later on,
for casting the guns solid. These were then bored by
a device practically similar to the one above mentioned.
Later on still, an improvement was introduced, by which
Figs. 529 to 541, Plate XCVI.. illustrate the series
of naval guns in use at that early time, ranging from
the short 4-pounder to the heavy 36-pounder; Figs. 542
to 553 are a similar series for land service, from the
2-pouiider Held gun to the 24-pounder siege gun. All
these types were manufacturée! at Creusot. The importance
of this place at the time is indicated by the faet that the
Fig. 554. Mitrailleuse, De Reffye System, 1870.
Fig. 555.
Field Guns, De Reffye System, 1870.
the guns were placed on horizontal supports, and caused
to revolve, the boring bits remaining fixed. Series of
boring bits were used successively, each one inereasing
the diameter of bore by 6 or 8 lines, the exact size being
oiven by a broaching bit. This method was again
improved by boring the gun at one operation to very near
the exact calibre, the final trueing cut being given by
a broaching bit.
celebrated technician, Gaspard Monge, in his remarkable
work entitled “ Description de l’art de fabriquer les canons,
faite en exécution de l’arrêté du Comité de Salut Public du
18 pluviôse de l’an 2 de la République Française, une et
indivisible,” several limes mentions the Creusot Works
as having contributed, even in those relatively reinote
times, to the progress realised in metallurgy and construc-
tion, especially as regards the military arts.