The causes of the difference between the two kinds of steel the author attributes to differences in the structure of the ingot due to the agent used in “chemical consolidation,” which may be either manganese or silicon, which structures are illustrated by photographs of ingot fractures.  When silicon is used there is a tendency to unsoundness about the exterior of the ingot, which is surrounded by a honeycomb-like cellular casing of greater or less depth; while with manganese the vesicular cavities are more or less dispersed through the whole substance, or concentrated toward the interior of the ingot.  Rails made from the former are, therefore, more likely to contain unsound portions near the outer wearing surface, and to give unsatisfactory results in wear, than those from the latter; but as the test pieces are usually cut from the center of the railhead, the tensile resistance of the interior may be equal to or surpass that of the superior material.  In summing up his observations the author concludes that the method of tensile testing is mainly of value in determining the quality of the material, but that for the finished product properly arranged falling weight tests are necessary.  He also considers that the test pieces should be flat bars of 2.5 to 3.5 centimeters in area, cut as near as possible to the outer surface of both head and foot of the rail.  He reprobates especially the research for microscopic imperfections (mikrobensuecherei) upon the fractured surfaces, as an annoyance to the producer, and perfectly useless to the consumer.—­Stahl und Eisen, vol. iv., page 608; through Proc.  Inst.  Civ.  Eng.

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A NEW FORM OF SMALL BESSEMER PLANT.

By Mr. A. TRAPPEN.

The success of the Bessemer process when carried out on the small scale at Avesta in Sweden, as described by Professor Ehrenwerth, and subsequent experiments of a similar kind made at Pravali, in Carinthia, and elsewhere, have led the author, who is specially occupied in the building of Bessemer works, to design a plant suitable for operation upon small charges.  This consists essentially of a converter about 1 meter outside diameter, and 1.5 meters high, connected by a single trunnion to a horizontal steel shaft carried by the arm of a hydraulic crane which is very similar in character to the ladle crane of a large sized converter.  The sweep of the crane is such as to allow the converter to be brought close up to the tap hole of the blast furnace or cupola, so that the use of open gutters for the fluid metal may be avoided as much as possible.  The converter is turned on its axis by a screw and worm wheel, which is manipulated by a workman standing on a platform at the opposite arm of the crane.  The blast is brought in from above by a pipe down the central pillar of the crane, which is connected with the blast-main by a flexible tube and packed joint.