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 at a pressure of less 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 can 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. I 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. 



Since 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.* — Boston Daily Advertiser and 

 Patriot. 



London, 18th Oct., 1839. 



34. Medical and Physiological Commentaries, by Martyn Paine, M. 

 D., A. M., in two vols. 8vo., pp. 716 and 815. New 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 a passing notice. 

 Its contents are, I. Vital powers, in three sections and an appendix; 

 the subject is treated at more than usual length. II. Philosophy of the 

 operation of loss of blood, in fifteen sections, with two appendixes. III. 



* Drawn up by Wm. Wheelwright, Esq., now engaged in introducing steam' nav- 

 igation from England to Chili, across the isthmus by rail road. 

 Vol. sxxix, No. 1.— April- June, 1840. 27 



