97 
Case 4 B. — Direct process wrought iron. The example 
shown is over 2000 years old, and was made directly from the ore 
without passing through the stage of pig iron. 
Cases 4 C and E>, — Fractures and test pieces of open 
hearth steel from Avesta, Sweden, showing the variation of texture 
and strength with the composition. 
No. 5. — A bar of open hearth steel in which a knot has been 
tied cold, as a test of the quality of the material. 
Case 6. — Sections of steel bars, rails and structural beams, 
from Spain, donated by Sociedad de Altos Hornos y Fabricas de 
Hierro y Acerro de Bilbao. (The Bilbao Iron and Steel Manu- 
facturing and Blast Furnace Co.) 
Case 8. — A series of fractures of crucible steel from the 
Dannemora steel works of Sheffield, showing the relation of com- 
position hardness and the appearance of the fracture. 
Case 9. — Bars of mild open-hearth steel tied cold into knots 
as a test of quality. 
Case 10. — Welds of brass and bronze to steel. The ends to 
be welded are heated in a gas furnace until nearly molten and 
then are pressed together. 
No. 11. — Wires for various purposes. On the wall are speci- 
mens showing the process of drawing wire. 
Case 12. — A collection of all grades of scrap-iron, steel and 
metal. It contains samples of different grades of iron and metal 
as it is sorted on leaving the scrap-iron dealer’s yard. 
Nos. 13, 14 and 15. — Models of three types of hot blast 
stove used for heating the air delivered to the blast furnace. 
No. 16. — Model of a rolling mill for rolling structural iron 
and steel. This mill rolls the largest beams of any in Germany. 
No. 17. — Model of machinery and annealing furnaces used 
in preparing molds for cast iron pipe. 
No. 18. — Model of a rolling mill. The three models. Nos. 
16, 17 and 18 show portions of the iron works of Gebruder Stumm, 
Germany. 
Upon the walls there is a series of charts illustrating the 
kinds of furnaces used in the manufacture of iron. 
