No. 112.] 893 



workmen cease their operations on many of tlie articles wliich 

 they produce. 



No. IV after being brought to a uniform size, was upset for 

 about three inches in the middle and was then annealed and 

 cooled slowly. 



No. V was drawn out, cut in the middle and welded together. 

 This sample was only G^- inches long. 



All thes^ bars- were then carefully gauged both in breadth and 

 thickness, at every inch of their lengths, before commencing the 

 trials of tenacity. The machine employed in testing them, was 

 the same which had been used in experiments made by the re- 

 quest of the Treasury Department on the strength of materials 

 for steam boilers. 



The following table will be understood without any other re- 

 mark than that the breaking weights in the 5th column, are cor- 

 rected for friction of the machine. The specific gravities of 

 several of the Iragmentsof each bar, after it had been broken up, 

 are given under the head of observations, and may serve as well 

 to illustrate the general character of the iron in this respect, as 

 to indicate the effect of the several methods of pre2>aration on 

 the density of iron. 



The following experiments confirm the evidences already ad- 

 duced of the great toughness and ductility of this variety of 

 iron. Besides the facts mentioned under the head of Obscrva- 

 iio7is, in the 7th column, we may add, that after the first fracture 

 on each bar, a measurement was taken between two of the inch 

 marks still remaining on one of its parts, and the following re- 

 sults obtained, viz: 



No. I. In original length 6 inches, had elongated, .87 in., = 14.5 per cent. 

 No. II. do do 4 do do .2 in., = 5 do 



No. III. do do 5 do do .6 in., = 12 do 



No- IV. do do 4 do do .2 in., = 6 do 



