24 Molesworth’s pocket-book
Tenacity of Wrought Iron and Steel.
Breaking Weights in Tons per Square Inch of
Original Section. Fractured Section.
Highest Class. Lowest Class. Highest Class. Lowest Class.
Steel bars for tools .. .. 59-3 45 62-1 59-1
„ „ rivets and bolts 47-9 41’1 70-9 62-2
1 „ puddled steel Steel plates 31-9 28 49-7 31-8
44-3 32-3 51 35-7
Iron bars, Yorkshire .. .. 29-6 27 58-8 51
„ „ Staffordshire .. 28 24'7 65-4 33-6
„ „ Lanarkshire.. .. 28-9 20-8 52-6 21-4
„ ,, Lancashire .. .. 27 24 46'6 38-5
„ „ Swedish .. .. 21-5 21-3 66'8 54
„ „ Russian 25’3 22*1 34-7 32-2
„ „ Scrap 24-7 17-2 42 18*8
,, „ South Wales .. Iron plate, Yorkshire .. .. 17-2 13'2 17-6 13-3
25*3 22 34 24-8
„ „ Staffordshire .. 24'1 20-3 27'4 22-3
„ „ Lanarkshire .. Iron straps and angle-irons for strap building .. .. 22-9 18-6 27 19
25 18-5 30 20-5
Angle-iron, Lanarkshire .. 25 23'1 32 28
„ „ Staffordshire .. 25 22-3 31'9 26
This Table has been compiled from the valuable
experiments of Mr. Kirkaldy, which have thrown
much light on the rules which govern the fracture
of iron. Amongst other points the experiments
have shown conclusively—
1st. That the breaking strain of iron and steel
does not (as hitherto assumed) indicate the quality
—a high breaking strain may be due to hard
unyielding character, or a low one may be due to