Mechanical Science. 151 
the cause of English iron being inferior to Swedish, for particular 
purposes, is pointed out. 
In the Seventh Section we are shown how to obtain some of the. 
most useful practical rules from the first principles that are fur- 
nished by experience. 
The Eighth Section treats of the stiffness to resist lateral strains, 
with its application to some interesting practical cases. 
The Ninth Section is on the strength and stiffness to resist tor- 
sion or twisting, with its application to machinery. 
The Tenth Section treats of the strength of columns, pillars, and 
ties, with some new examples. It may be useful to remark, that 
the most refined methods of analysis have been applied to the same 
subjects by Euler, Lagrange, and other continental mathemati- 
cians, without arriving at results more accurate, more simple, or 
more convenient in practice. 
In the Eleventh Section the author considers the resistance of 
beams to impulsive force. In this section will be found many im- 
portant rules, with examples of their application to the moving 
parts of engines, bridges, &c., wherein the advantage gained by 
employing beams of the figures of equal resistance is shown. 
The Eleventh Section is followed by an extensive Table of the 
Properties of Materials, and other Data, often used in Calculations, 
arfanged alphabetically, and in this Edition much enlarged. By 
means of this table the various rules for the strength of cast iron, 
contained in this work, may be applied to several other kinds of 
materials. 
A Note, added at the end of the table, on the chemical action of 
some bodies on cast iron, will be read with interest by those who 
employ cast iron where it is exposed to the action of sea water. 
4, On the Capillary Action of Fissures, ye.—M. Dobereiner has 
remarked a singular effect produced apparently by fissures. Hav- 
ing filled a large glass flask with hydrogen, and left it standing 
over water, it was observed some days after, that the water had 
risen in it above one-third of its capacity. The only cause for this 
effect that could be assigned was, the existence of a very minute 
fissure in the glass. Filled a second time and left over water, 
the fluid had risen in it above an inch and a half in twelve hours, 
and in twenty-four had risen two inches and three quarters, during 
which time the barometer and thermometer had not sensibly al- 
tered. In other experiments, vessels of other forms were used, 
and the water uniformly rose in those having fissures. 
When one of these vessels filled with hydrogen was covered by 
a bell glass, or when the vessels were filled with atmospheric air, 
oxygen, or azote, instead of hydrogen, no change took place. — 
M. Dobereiner considers the effect as due probably to capillary 
