76 
ent periods of time, well washed in water, and weighed. 
They were then heated in a kitchen oven and again weighed. 
The results are given in the table below. 
TABLE SHOWING THE INCREASE OF WEIGHT AFTER IMMERSION 
IN ACID. 
HYDROCHLORIC ACID. SULPHURIC ACID. 
Weight in Grams. 
Loss 
Gain 
Weight in Grams. 
Loss 
Gain 7° 
hy 
7. 
by 
Heat- 
ing. 
by Im- 
Quality. 
Before 
1 After 
Heat- 
in. a* 
by 1m- 
mer- 
REMARKS. 
Before 
After 
mer- 
sion in 
Heating 
Heating 
sion. 
Heating 
Heating 
Acid. 
1 
Steel 
124 
49-81525 
' 49 81500 
■00025 
•000502 
} Appearance of fracture 
f crystalliae, speckled 
50-56990 
50-55516 
•01474 
•029156 
2 
Mild Steel. 
126 
47-36490 
1 47-36020 
■00470 
•009923 
T and white ; after heat- 
J ing, finer and greyer. 
43-85970 
43-84990 
"00980 
•022350 
3 
Best Iron. . 
122 
47-48030 
47-47495 
•00535 
•0112601 
43-25005 
43-23965 
•01040 
■024052 
I 
>- Annealed. 
4 
Char. Iron. 
125 
43-20994 
43-20020 
•00974 
•022540 
X 
42 34002 
42-32974 
•01028 
■024285 
Total. .J 
187-87039 185 '85035^ '02004 
•010659 
180 01967 
179-97445 
•04522 
•025126 
In acid 5 hours, 
then washed several times in water and heated 18 hours 
in an oven. 
5 
Mild Steel. 165 
78-69240 
78-65170 
•04070 
•05187 
71-36530 
7P32490 
•04040 
•05664 
6 
Best Iron. . 
165 
81-68530 
81-67220 
•01310 
*01604 
85-98500 
85-94000 
•03500 
•04072 
7 
Char. Iron. 
165 
78-69240 
78-65170 
•01595 
02028 
84-09020 
84-07515 
•01505 
•01796 
Total 
239-07010 
238-97560 
■08975 
■02918 
24114050 
241-34005 
•09045 
•03747 
In Acicl 3| hours, then well washed in water. Heated 18 hours. 
8 
Steel 
165 
80 08010 
80-06770 
•01240 
•01548 
In Acid 12 hours. 
Heated 30 hours. 
9 
Steel. 1 
180 
7910020 
79'09005 
•01015 
01283 
10 
Mild do. . . 
182 
f Very slightly rusted 
\ after heating. 
77-56980 
77-56990 
-■oooio 
11 
Best Iron. . 
155 
74-92055 
74-91722 
•00333 
■00440 
12 
Charcoal . . 
158 
61-42040 
6P41990 
•00050 
‘000814 
13 
Ditto .... 
120 
8715715 
8715500 
■00215 
•00245 
In Acid 12— 
-13 hours. 
then steeped in water for 10 hours. 
Heated 24 hours. 
In all cases except one they were found to have lost in 
weight, and the exception was probably owing to the 
increased weight caused by a slight coating of oxide over- 
balancing the loss occasioned by heating. 
