320 British Association for the Advancement of Science. 
Dr. Lardner addressed the meeting on Steam Navigation and 
on a self-recording Steam-Journal. Dr. L. said that it was a 
matter of no real importance how far any opinion which he might 
have formerly expressed on extended navigation was right or 
wrong, except so far as it had been made a personal question. He 
had, indeed, expressed a discouraging opinion as to the probability 
of ever maintaining an unbroken intercourse- by steam naviga- 
tion between Great. Britain and New York, but he had never de- 
clared that it was a physical impossibility. He confessed that 
the success of the Great Western had shaken his former opin- 
ions, and should the same success continue throughout the entire 
year, he would be the first-to come’ forward and acknowledge 
himself. completely i in error. He then gave an account of his in- 
strument, termed a steam-journal, by which he proposes to reg- 
ister every five minutes, the following varying phenomena, on 
which the efficiency and performance of steam engines depends: 
—the presstire of the steam between the slides and the steam 
valve—the pressure in the boiler—the vacuum and the quantity. 
of water in the boilers—the saltness of the water in the boilers,— 
the velocity of the paddle-wheels—the draft of the vessel—the 
trim of the vessel—the rate of the vessel,—the course of the ves- 
sel,—the apparent force and direction of the: wind. All these, — 
excepting the course of the vessel, it.is.intended to sia oor: by 
self-acting mechanism. 
_ Mr. J. 8. Russell followed with an essay on the same general 
subject, and insisted on the propriety of eee steamboats sharp. . 
Iron adie with copper tubes, appeared: to him the best. 
Mr. Fairbairne described machinery for cee boiler plates, 
by which the work is done. better and much more speedily than in 
the usual methods.—Mr. B. Green gave an account of the con- 
struction of timber viaducts.—Prof. Willis described a method re- 
cently introduced by Mr. Hawthorn, of working the valves of a 
locomotive without the usual eccentrics.—Mr. J. T. Hawkins 
described several methods of filtering water.—Several communi- 
cations were offered which could not be read for want of time, 
viz. Mr. Reed; on an improved safety hook and bow for coal-pits : ~ 
Mr. Glynn, on. the waterworks of Neweastle: Mr. Wake, on @ 
new paddle-wheel ; Sir C. Monteith, on a new tram-road ; on an 
improved kitchen grate: Mr. Fourness,.on coal mine ventilation : 
Mr. Dobson, on a method of making bricks of every required color. 
Bee) rosetta ar wn 
: aaa ip 
Reason. 
