The Sun.
London, England, 1863-08-06 00:00:00

The Institution of Mechanical Engineers,

---
EngineersTh e p provincial
esession of h
Liverpool; Mr. W. Clay presiding. An elaborate paper
was read by Mr. John Vernon, of Liverpool, " On the con-
struction of iron ships." The points of advantage in
don Tuesday, the Ins tiattusti 011 ofe or Mgeni
sh
of iron vessels over those of wood were superiority
av favour
of
strength, greater durability, less cost, together with greater
t.GeeaHaellal,
fr
carrying capability, greater facility of construction, and more
certain supply of material. The Gieat Britain wasagd
example of the strength and power of resistance possessed
ra
good
by
iron vessels; for, al, hough she lay stranded in Dund ru
Bay for nearly 12 months, and subjected to a severe strain,
she was ultimately drawn off in safety, and found capable
of efficient repair. Mr. Vernon next drew attention to the
importance of iron in the construclon of the screw colliers
whioh had recently come into use, and which were fur-
nished with a chamber throughout the entire bottom of the
hull for the carrying of water ballast, which could be
pumped in and out, and whioh was a most economical sub-
stitute for ordinary ballast. He then described the uses
of iron for flat-bottomed boats intended for river navigation,
and particularly the system called " Bourne's Indian
river iotin," employed on the Ganges and Indus; where
by Convex bows and concave sterns an articulated train
was formed by barges. It was not, however, found
I to answer so well as expected, in consequence of the currents
of the rivers preventing a due control of the steering appa-
ratus. The question had arisen what advantage was ob-
tained by the use of steel instead of iron in the construction
of ships. Steel would hear a strain of 40 tons per inch, and
the best iron only 20 tons. In practice, however, it was not
considered advisable to reduce the proportion of steel lower
than two thirds the weight of the iron. There was no ob-
jection h a mechanical point of view to steel when it came
up to the professed standard, but in a commercial point of
view steel was found to be much more costly. The use of
steel was not of course accompanied by any increased in-
ternal capacity. Mr. Vernon states that the objection to
iron ships, on the ground of fouling at the bottom, and the
derangement of the compasses by the local metallic attrac-
tion, might be gradually overcome by improved inventions
for coating, and by improved knowledge of appliances to
correct the deviation. Some discussion followed, after
which a vote of thanks was awarded to Mr. Vernon. The
papers which followed were, " On the effects of surface con-
densers on steam boilers," by Mr. James Jack, of Liver-
pool ; and " On the mechanical ventilation and warming of
St. George's Hall," by Wm. Mackeneie, of Liverpool
After the discussions, the members occupied themselves
with the inspection of some of the principal engineering
establishments of the town.

GENERAL M'CLELLAN.—An admirable life-size
model of this distinguished General, late commander-in-
chief of the Federal army, in military costume, has, within
the last few days, been added to Madame Tussaud's Ex-
hibition, in Baker-street, and we doubt not but that most
of the Americans now residing in this country will avail
themselves of the opportunity thus afforded to pay a
visit to the historical gallery on such an interesting occa.
sion, where likewise is to be seen a model of President
Lincoln.