ON THE STEENGTH OF PILLAES OF CAST lEON. 
897 
Experiment 6. — Square Pillar, Calder Iron, No. 2. 
Side of square from eight admeasurements 2*194 inches. 
Weight of Pillar 146 lbs. 5 oz. =146*312 lbs. 
Weights laid on. 
Deflections. 
Decrements of length. 
lbs. 
inch. 
inch. 
20693 
*19 
*068 
25397 
*23 
*081 
30101 
*27 
*094 
34805 
*35 
•108 
39509 
*47 
*122 
44213 
*69 
•142 
47976 Broke. 
— 
— 
Broke about 5 inches from the middle by bending in the diagonal, 
lbs. lbs. lbs. lbs. 
Whence 146*312 : 150 : : 47976 : 49185 =reduced breaking weight. 
The figures standing over each other represent the pillar, at the place of fracture, 
near the middle ; and the small additional piece, that of the part broken out from one 
corner by compression. 
Experiment 7. — Square Pillar, Calder Iron, No. 2. 
Side of square from eight admeasurements 2*221 inches, 
Weight of Pillar 149*25 lbs. 
Weights laid on. 
Deflections. 
Decrements of length. 
lbs. 
inch. 
inch. 
20693 
*14 
•077 
25397 
*17 
•090 
30101 
•21 
•103 
34805 
•27 
•115 
39509 
•34 
•128 
44213 
•45 
•143 
48917 
*64 
•160 
53621 
1*14 
•195 
Broke in about a minute with this weight, bending in the direction of the side, 
lbs. lbs. lbs. lbs. 
Whence 149*25 : 150 .* : 53621 : 53890 =reduced breaking weight. 
lbs. 
53890 + 49185 
:51537 lbs., 
the mean strength of a square pillar 150 lbs. in weight, its length being 10 feet. 
The vertical figures represent the pillar at the place of fracture, which in this case 
was different in form from the preceding one, and along the side ; these and the smaller 
figure, representing the transverse section, show the small size of the compressed part. 
