EXPERIMENTAL RESEARCHES ON DRAWN STEEL. 
21 
Table VII.—Influence of Time on the Temperature Coefficient and Residual 
Magnetic Intensity of Drawn Steel. 
H 30 Piano Wire, 8 centims. long. 
Date. 
Residual intensity. 
Temperature 
coefficient, 
a. 
Remarks. 
Initially. 
Finally. 
X 10--' 
1897. 
May 21. 
474 
34] 
+ 0-15 
Magnetised for the first time. 
,,36. 
— 
— 
— 
Boiled for 2 hours. 
Jiuie 1 . 
— 
-- 
— 
„ 9. 
265 
264 
+ 0-15 
July 5. 
255 
255 
-0-14 
September 10. . . 
210 
240 
-0-40 
October 18 ... 
200 
— 
-0-40 
' 1898. 
s July 11. 
222 
222 
-0'47 
! „ 11. 
475 
349 
+ 0-05 
Remagnetised. 
„ 14. 
341 
338 
+ 0-12 
Boiled for 44 hours. 
„ 17. 
--- 
— 
— 
15 
5? V )) 
„ 18. 
333 
330 
+ 0-00 
October 10, . . . 
324 
320 
aO-09 
„ 14. . . . 
310 
307 
+ 0-07 
1899. 
June 16 .... 
322 
322 
+ 0-61 
October 30 . . . 
317 
316 
+ 0-58 
1900. 
March 29 . . . . 
312 
311 
+ 0-42 
Second Sample. 
H 30 Piano Wire, 8 centims. long. 
1898. 
' October 14 ... 
474 
— 
— 
Magnetised first time. Heated 
1 
: „ 21 . . . 
00 
■to 
364 
+ 0-33 
and cooled 12 times. 
; „ 22 . . . 
— 
— 
— 
Remagnetised. Boiled for 3 
November 9 . . . 
345 
321 
+ 0-31 
hours. 
Heated and cooled 12 times. 
„ 14. . . 
335 
334 
+ 0-32 
1899. 
June 16 .... 
341 
337 
+ 0-76 
November 3 . . . 
332 
331 
U * 6o 
1900. 
April 9 . 
331 
327 
+ 0-59 
