* 
Miscellanies. 209 
We had the full benefit of the tide down, and accomplished the dis- 
tance in seventy-one and a half minutes, and allowing for a tide of 
three and a half miles per hour, we made fifteen and a half miles 
per hour through the water, working ata pressure of Jess than four 
pounds, with two ninety horse engines. The very slight vibration was 
a subject of general remark. 
12. Another argument against iron steamers, is the difficulty of ma- 
king them stiff. It seems very absurd to say that an iron form cannot 
be rendered equally stiff and firm as one of wood. An iron steamer 
is less likely to bend or hog than a wood steamer. The pressure is 
on the edge downwards, and it would be scarcely possible to produce 
such an effect, unless the iron be broken, for the rivetted part may be 
considered equally strong as, or even stronger than the plate. 
13. The construction of iron vessels ean be rendered perfect only 
by practice, time, and experience. The drafts or models which I have 
seen, admit of many improvements, but as to their eventual general 
adoption I have no question. To many it appears such an innova- 
tion upon custom so long established, that it is condemned without 
cause or reason. JI am perfectly persuaded that iron steam vessels 
can be navigated for one half the expense incurred at present in wood 
vessels. The opinions of the most practical and scientific men in 
the kingdom are universally in favor of iron as a substitute for wood 
in the building of steamers, both on account of its greater security, 
and durability, and also of its extraordinary economy. 
ince the foregoing was written, I have received a report from the 
Seine respecting the iron steamer Aaron Mont—that she was in cap- 
ital condition, very fast, and performed her voyages to the satisfaction 
of the proprietors ; she was built in the year 1817, has run twenty-one 
years, and no signs of corrosion.*—Bosto n Daily Ee ks tser and 
Patriot. 
London, 18th Oct., 1839. 
34, Medical and Physiological Commentaries, by Martyn Patne, M. 
D., A. M., in two vols. 8vo., pp. 716 and 815. = York, Collins, Keese 
& Co. London, John Churchill, 1840. 
We have received from its author a copy of this extended work just at 
the close of our number, and too late for any thing but gee a 
Its contents are, I. Vital powers, in three sections and an appendix; 
the subject is treated at wise than usual Jength. II. Philosophy of the 
operation of loss of blood, in fifteen sections, with two appendixes. III. 
a lank cio eenoarenegionen 
* Drawn up by Wm. Wheelwright, Esq., now engaged in Levene steam nav- 
igation from England to Chili, across the isthmus ars rail road 
Vol. xxxrx, No. 1.—April-June, 1840. 
