388 Progress in Science. [July, 
puddling furnace are retained, so that the improvements may be adapted, at 
moderate cost, to the working plant at present in use. The ordinary hearth 
is replaced by a revolving chamber, of which the best form is that of two cones 
placed base to base; it is constructed of wrought-iron, with hollow cast-iron 
trunnions mounted on rollers, which in their turn rest upon a carriage running 
on wheels in a direction across the axis of the furnace. Motion is imparted 
by an ordinary engine, and the machine makes from three to eight revolutions 
per minute. The chamber is protected internally by a lining of bricks of oxide 
ofiron. In order to remove the ball of iron when ready, the chamber is moved 
from its normal position, and being slightly tilted the ball is readily pushed 
out through the open trunnions. To avoid cooling the chamber by influx of air 
through the space formed at the joint of the trunnions—for a certain amount of 
play must be left to allow for expansion—the opening against which the 
trunnion works is formed by two cast-iron rings enclosing an annular space, 
which communicates by a flue or pipe with the space immediately above the 
fire-crate. By the draught thus produced in the annular space the air which 
leaks in at the joint is carried off by the most dire& route, and consequently 
little or no air gains admission to the working chamber. This method of 
checking the ingress of the air is found to be of great importance in the 
practical working of the machine. 
Mr. J. Head, of Middlesbro’, has described at some length the Newport 
puddling furnace, of which a model is exhibited in the International Exhibi- 
tion. The chief feature of this furnace consists in its economy of fuel. 
Records of the working show that a given weight of puddled iron may be 
produced by little more than half the quantity of coal required in the ordinary 
furnace, while there is also a saving of about 10 per cent of iron. Thus the 
average consumption per ton of puddled bar was 12cwts. 3 qrs. 63 Ibs. of coal, 
and 20 cwts. 2 qrs. 24 lbs. of refined iron; in other words, the puddled bar 
weighed 96} per cent of the iron charged. The fettling employed was made in 
a tap furnace from various cinders and scraps, and contained no hematite or 
other expensive ores. 
It is almost needless to mention at this date that the detailed reports on the 
now celebrated Danks furnace, by Messrs. J. Jones, Snelus, and Lester, were 
submitted to the Iron and Steel Institute at their last meeting. ‘These reports 
of the individual commissions supplement the general joint report dispatched 
from America, and referred to in our Chronicles last quarter. It is gratifying 
to learn that the high opinion expressed by the Commissioners has been fully 
borne out by the results which have already attended the working of the 
furnaces erected on this principle in England. The first of the new furnaces 
was put up by Messrs. Hopkins, Gilkes, and Co., of Middlesbro’, and has 
worked with great success. Ina purely scientific journal we may perhaps be 
spared the pain of referring at any length to the technical objections which 
were raised in certain quarters against the validity of Mr. Danks’s patent- 
rights in this country. 
Few points in the metallurgy of iron are more important than the elimina- 
tion of phosphorus from pig-iron containing this prejudicial element. The 
extent to which it may be removed by the Henderson process is well seen in 
some determinations recently made by Mr. E. Riley, and published in the 
“« Chemical News” (May 17, p- 237). At a trial made at the Blockhairn Iron 
Works, in Glasgow, on the 23rd of last December, the charge consisted of 
360 lbs. of No. 4 Dalmellington pig-iron, roo lbs. of ilmenite, ro lbs. of man- 
ganese, and 42 lbs. of fluor-spar. The pig-iron contained 1°14 of phosphorus, 
but this was eliminated at such a rate that samples of the refined iron taken 
in succession at thirty, forty, and fifty minutes after fusion contained respec- 
tively 0°23, 0°15, and o12 of phosphorus. Finally, the phosphorus was so far 
removed that the wrought-iron contained only 0:07 per cent. On the other 
hand, the cinder yielded 0°52 percent. Asit was found that all the phosphorus 
had not passed into the cinder, some of it must have been volatilised during 
the refining. Samples of bar-iron and plate rolled from iron puddled under 
