APPENDIX B.

Table showing the results of the working of the saw-dust furnace at Munkfors during the year 1866, comparatively, with the results obtained from the charcoal furnaces of the Society of Uddcholm.

The table shows the results for the first year of working of the saw-dust heating furnace. The two coal furnaces served at the same time as reserves, and have only been worked when the other was under repairs. During the first six months the yield was 789 tons of bar-iron, and in the last six months 1,013 tons, of which 557 tons was during the last three months, or at the rate of 2,229 tons per year.

The column containing the consumption of carbon of wood not coked per ton is calculated on the assumption that a cubic foot of charcoal contains eight pounds of pure carbon, and that 50 per cent, of the richness of the wood in carbon is lost in coking. The column shows, therefore, the real consumption of carbon per ton of iron made.

All the parts of the furnace are easy to manage, and all the work is regular and solid. The reheating furnace is rarely repaired oftener than every five or six weeks; the repairs only require one or two days at most. The most frequent are only the upper portions of the regenerators, which require to be changed. The condenser is only opened and examined two or three times per year. The gas generator is not cleaned during the week, unless this precaution is rendered necessary by the use of impure saw-dust, or dust mixed with sand; and, in any case, this presents no obstacle to the work. Usually the cinders formed during the week are piled at the side of the neighboring wall every Saturday evening when the work is finished, and it is not necessary to undertake a careful cleaning or to remove the refuse, except when the generators are prepared. The tube of the conduit between the gas generator and the condenser requires to be cleaned every week; but this cleaning, which can be easily made during the working of the furnace, does not prevent the heating. Also generators of a larger size require cleaning much less often.

In comparing the consumption of fuel in the saw-dust furnace with that of the charcoal furnaces, it will be seen that the first was able to heat 3 cwt. of iron with the same quantity of combustible that the latter would have required for 1 cwt, and this though the former works with wet fuel.

The latest results of the saw dust furnace are as follows: From November 10, 1866, to April 18, 1867, or during 105 days of 24 hours, a yield of 926 tons of bar-iron, with a waste of 12. 04 per cent., and with 268 cubic feet saw-dust per ton of iron. One week showed a yield of 56. 18 tons, with 219 cubic feet per ton, the waste being only 9.9 per cent. At present the waste does not exceed 11 per cent.

APRIL, 1867.

Brand

Brand.

APPENDIX C.

TABLES OF EXPERIMENTS MADE BY DAVID KIRKALDY ON BESSEMER STEEL AND SWEDISH IRON.

General abstract of the results of experiments to ascertain the mechanical properties of eleven bars of billet-iron from the Degerfors Iron Works, Sweden.

General abstract of the results of experiments, &c.—Continued.

BENDING STRESS: DISTANCE BETWEEN SUPPORTS TWENTY INCHES.

Effects.

PULLING STRESS.

STRESS IN POUNDS PER SQUARE INCH.-EXTENSION AND SET, INCH.

STRESS IN POUNDS PER SQUARE INCH.-EXTENSION AND SET, INCH.

THRUSTING STRESS.

DAVID KIRKALDY.