FtBKUARY 2 1, 189O.J 



SCIENCE. 



121 



out of bar plates of 1 foot width. Three of these latter were 

 rolled out to two, thi'ee, and four times their length, to thick- 

 nesses of 6.1, 5.4,- and 3.1 millimetres: the other eight were 

 rolled in bundles, first in one direction, then at right angles to 



1 per cent of lead and .03 of one per cent of iron; the two for- 

 eign plates showed traces of antimony ; no other metals were ob- 

 served. 

 The first series of tests was made with a horizontal Rudeloff 



FI(J, 5. -TRIUMPH COMPOUND VALVELESS STEAM-ENGINE. 



this direction, test-pieces being cut out each time when the 

 length had increased by 500 millimeti-es. The final plate varied 

 in length from 1,210 to 4,710 millimeti-es, and in thickness from 

 1.1 millimetres to .6 of a millimeti-e. The chemical analyses of 

 the various plates agi-eed very closely : they all contained about 



testing-machine with scale-pan, screw, and nut-feed; the pris- 

 matic test-pieces, 20 millimetres (.8 of an inch) in width, being 

 fixed in caps, and tightened there by means of wedges. The 

 pieces fi-equently broke close to this clamp; and it was found that 

 the length of the wedge, and the distribution of the pressui-e, were 



