INDUSTRIAL PROGRESS DURING THE YEAR 1871. clxxix 



is a source of great annoyance to the founder. Dr. Kiinzel 

 claims, however, to have succeeded in causing this segrega- 

 tion to take place in uniform distribution throughout the 

 casting, and has taken advantage of the properties of the 

 product he obtains to construct therefrom bearings of rail- 

 way and other machinery. In heavy bearings, such as those 

 for marine engines, the valuable properties of Babbitt metal, 

 and other anti-friction alloys, are well recognized ; but these, 

 being generally soft, soon become distorted under consider- 

 able pressure accompanied by continual vibration, and fail 

 to sustain the journals in proper place. The machinist there- 

 fore resorts to the device of casting a hollow cage of hard 

 metal of proper form for the intended bearing, the cavities 

 of which he then fills up by casting into them the soft metal 

 alloy, which thus forms the actual rubbing- surface of the 

 bearing. The hard-metal cage thus supports the soft metal 

 within, and prevents its distortion or escape, save by surface 

 abrasion. The new phosphorized alloy of Dr. Kiinzel effects, 

 it is claimed, the same result. It forms its own supporting 

 cage for the soft bearing metal, which, as alluded to in the 

 outset, separates from it in the process of cooling. He claims 

 that these bearings combine the very small friction and non- 

 abrasion of the journals with the firm resistance to pressure 

 and stability of form of bearings of hard metals. 



We can not omit to record likewise certain important and 

 highly interesting discoveries concerning the behavior of 

 metals under stress, which have attracted much attention 

 during the past year, during which time they were fully de- 

 veloped. Professor Robert H. Thurston, in the course of 

 some experiments with an apparatus for determining the 

 tortional resistance of materials, which was provided with an 

 automatic registry, permitted a test piece of wrought iron to 

 remain in the machine strained far beyond its limit of elas- 

 ticity, with the view of determining, if possible, the existence 

 or non-existence of " viscosity " in the metals. The metal was 

 left under strain twenty-four hours, and had not then yielded 

 in the slightest degree: a fact that has an important bearing 

 upon the availability of iron and of steel (which behaves 

 similarly) for use in constructions exposed to severe strain. 



After twenty-four hours, there appearing no evidence of 

 further yielding, it was attempted to still further distort the 



