300 
Scientific Intelligence. 
my report to the Bureau of construction, equipment and repairs of the 
Navy Department, that the average gain of length of bolts of iron 
treated at the Washington Navy yard, by this same process, was 5°75 
per cent., and the gain 
of strength 16°64, making together the gain of 
value 224 per cent. The addition of 5°75 to 17:85, gives 23°6 per 
cent. for the total gain of value. In many instances the experiments 
made at the Franklin Institute proved the gain of length to exceed 7 
per cent. The report to the Bureau also confirms what had previously 
been observed, viz. that the total elongation of a bar of iron, broken in 
its original cold state, 
force would produce upon it if applied at a temperature o 
oree will moreover not break the bar at that temperature. 
is from two to three times as great as the same 
f 573°, 
which — 
tag sien 
le oo il 
Table exhibiting the effect of Heat on thirty-two varieties of Malleable Iron. 
Beal SS |S bole So! Se) ssl & mS |2se| S30 
Name and origin of the speci Ae Ee s£\2 ise Bee 32 ei 253 a 
° men of | s BES slE7 | ES5 = ao 208 
inure eel ee eeere|see| c2 ee. \°25| pees 
e32| 53 fales|-=| £22 | 5° gas |ono| hese 
‘ BEE Saighlee) sag | & 9 Og |-9S| Gee 
Be ¢ Basler See BS/SE5) Z| 258 \6e5| Beez 
_|Salisbury, (Conn.) gun bar, 192. 4) 1| 559,271 60,459 65,090) 8.2) + 2:0 
ramee, (Mo.) bar iron 166 528 | .7 353,775.54 8 09 
Phillipsburg, (Pa.) wire, 4 4/79, 488 0-4 Bd 09 
Ellicott’s Baltimore boiler plate,| 128 770 |: 5|56,644'56, 7| £00 
' “ ‘“ “ | 130 d "s 58.8 9} — 12 
Salisbury, (Conn.) gun bar, 2 q 7/59,654 60,323 T| + th 
& a “ 200 590 | 4 9/59,032 62,9 5 | + 66 
Swedish bar iron, ‘ 58,01259,77 + 30 
Nashville, (Tenn.) bariron, | 172 520 | % 5|54,934)58,4 5 | + 64 
alisbury, (Conn.) gun bar, 206 : 10/58,305,58,8 + 10 
Ellicott’s Baltimore forged bar,| 118 1/57 ,182.63,322 107 
Spang & Son,* ham’d plate, 90 766 | ¢ 1 57,664 8 — 494 
Blake & Co." ham’d plate,” | 104 572 | ( 60,532 62 iis seeks 
Salisbury, (Conn.) gun bar, 194 4 55,977 no hot frac.| . 
ns “ 208 4) 2| 8154'64460,215 5 | 10-2 
ot em “ 204576 | 5| 2} 5158,200164 10-0 
é “ “6 196 y, 6 57,433 4:5 
English “best-best” cable bolt,| 152 3} 1] 10/62.466 no hot frac. 
Pan. 's Pittsburg ham’d plate, | 86 ‘ 56762155. 194 44 
ashville, (Tenn.) bar iron, | 178 : 6152.729158.534 5 | 411-0 
ge iltenberger,* piled) 82 574 | 4 2155,426 60 33! + 5% 
ashvile, (Tenn.) bar iron, | 174 562 | 4 2|52,194'59,623/62,433|19:'8 | +142 
Ellicott's Baltimore boiler iron,| 126 |55: : 3161,519166,450|73, ' + 80 
Sag a s Pittsburg boiler,| 114 1630 3/53; 3)56,159 64,926 20°6 + 44 
ae, )b j 564 |: 9 49.974152.158)58,126 20-6 43 
fei: as Tenn.) bar, 170 [578 | -5| 1| 552,40659,192\62,951/21- 129 
esan sable Der, 0 584 | 5] 1| 3176,071/77,161|92,470)21-5 | + 14 
—. 0. ‘ 162 [576 6| 1| 4/43,386)50,067|53 23° 4 
icott’s hammered bar, 18 || 1/53;17656,570169,767/25°8 | + 
Salisbury, (Conn.) gunbar, | 198 ae Gee 52,873 60,988 66,685 
Maramee, (Mo.) bar, 60 5} 2] 4/45,586)51 ,437|58, 25228 
ake’s Pittsburg ham’d plate, | 106 6| 1| 4)52,937|58,284165,425|28 
Mean, 7 129) 36 |153 ean 
