ON THE MANUFACTURE OF IRON. 749 
three diameters of the boshes to the entire height; but no great importance 
can be attached to this ratio, inasmuch as the furnaces continue to work well 
long after the destruction of the lining has greatly altered the dimensions 
just given. One attempt has been made here to employ Alger’s furnace, in 
which the circular horizontal section is replaced by one of an elliptic cha- 
racter. In this form the iron is tapped, and the slag allowed to run, from 
the back as well as from the front of the furnace. At the Stockton Iron- 
works, where the system has been tried, the major axis of the ellipse is 12 feet 
and the minor 53 feet in the hearth ; the higher part of the furnace (which 
is an old one altered) remains circular. The owners do not find it expedient 
to work it from both sides, as is proposed by the patentee, neither has it the 
large dimensions he recommends. It is therefore premature to offer any 
opinion on the merits of the plan from the experience of this district, which, 
however, hitherto has not been such as to warrant the conclusion that a de- 
parture from the old shape is advantageous. The blast in the North of Eng- 
land is introduced generally by three or four tuyéres, at.a pressure varying 
from 3 to 4lbs. per square inch, and at a temperature of about 600° to 700° F. 
The production of a furnace is from 200 to 220 tons weekly, although more 
than this quantity has been frequently obtained. 
Quahty of Iron from Cleveland Ironstone.—Notwithstanding the composi- 
tion of the slags already spoken of, the furnaces drive with great ease and 
rapidity—the cinder flowing, when the make is foundry iron, perfectly liquid, 
and of an intense white heat. 
For foundry purposes the Cleveland iron was at first objected to from its 
chilling quickly in the “ ladle,” when compared with the makes of Scotland, 
and producing more “ scum ”’ than the metal from that country. 
The writer had this scum analyzed at the Clarence Works, and found it to 
consist of— 
Silicate of iron 42°10 
Protoxide of iron 8°32 
Mon $73 s es aa 42°02 
Carbon oa ace 1°93 
Protoxide of manganese 2°82, 
Lime ... Re - “49 
Magnesia “10 
Phosphorus Ir 
Sulphur *23 
Titanic acid 88 
100°00 
The furnaces of this district have little tendency to produce what is techni- 
cally known as “glazy iron.” Some years ago one of the Clarence furnaces, 
however, did run a quantity of this kind of metal. 
Two samples of it were 
analyzed, and their composition was ascertained to be as follows :— 
No. 1 Pig. No. 1 Pig. 
Tron ae so “ -- 88°18 90°70 
Carbon combined ... dea = "79 “71 
Do. uncombined 2°59 2°68 
Silicon see ore 5°13 5°13 
Manganese... ane oa ot 7 iy “56 
Sulphur... a os nec "17 "23 
Phosphorus ac I'l2 1°12 
Titanium ... aoe Ae ae 26 “18 
Calcium... ies St, Ree 22 *20 
Magnesium... 33 Sa 4 "06 "03 
Authority..,......... Clarence Laboratory. 99°29 IoI"54. 
