226 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 
The process of producing reconstructed rubies by means of the 
oxy-hydrogen blowpipe is, roughly, as follows: The residue from 
cutting rubies and small worthless stones is broken into coarse sand, 
asmall quantity of which is placed on the center of a disk of platinum; 
this is then carefully brought to the fusion point, care being taken 
at this stage not to raise the temperature to such an extent as to 
melt the platinum support. As soon as this mass is fused it serves 
to protect the platinum, and the reconstructed ruby can be built 
up on it by adding the fragments of ruby one at a time by means of 
small platinum forceps. These pieces have to be dropped on with 
great care in order to secure incorporation with the mass and pre- 
vent as far as possible the formation of air bubbles. It will be readily 
understood that this process is a tedious and laborious one, and, in 
fact, the formation of masses of sufficient size to yield large stones 
on cutting is a matter of such difficulty that the cost of production 
is very high. 
Just about seven years ago, however, Verneuil! overcame this 
restriction when he hit on the extremely ingenious idea of intro- 
ducing the raw material through the blowpipe, and thus placing 
it on the support automatically. The diagram (pl. 2, fig. 1) shows 
the principle of his apparatus. The blowpipe is arranged vertically 
over a small insulated chamber containing the support on which the 
mass is to be built up. The oxygen tube communicates at its upper 
extremity with a funnel-shaped hopper, in which is suspended a 
small sieve filled with the raw material, which is rhythmically shaken 
by means of a small hammer actuated by an electromagnet or cam. 
Each time the hammer taps the support of the sieve, causing it to 
vibrate, a small quantity of the powder falls through into the tube 
below, and, carried along by the gas, passes out at its lower extremity 
into the zone of flame, where it is immediately raised to the fusion 
point, and falls as a meited globule on to the support below. 
As seen in the diagram, this support is arranged with a screw 
adjustment, so that as the mass of corundum is gradually built up 
by the constant addition of fresh globules the surface can be kept 
at a constant level, and the portion already formed removed from 
the zone of heating so as to allow it to stiffen. When the apparatus 
is first started the blowpipe is adjusted so as to give a comparatively 
cool flame, and the powder is admitted slowly. By this means a 
small ‘‘stalk’’ is formed, which insulates the mass from the support 
and prevents the fusion of the latter. When this has been formed 
the full pressure of the blowpipe is put on and the rate of admission 
increased, with the consequent formation of a ‘‘boule,” as it is 
termed, having the shape of a pear, as illustrated in plate 2, figure 2. 
1 “Mémoire sur la reproduction artificielle du rubis par fusion,”’ M. A. Verneuil, Annales de Chimie et de 
Physique, September, 1904. 
