Mr Scoresby on the Impre^mtiwi of Wood with Sea-Water, 111^ 
in this way I expected that a much higher degree of impregna- 
tion would be obtained. 
Before examining the plug, I sank the bottle to the depth of 
2928 feet ; but here the pressure unfortunately being too great 
for the strength of the glass, the bottle burst, and only the ring 
of the neck encompassing the plug came up* The result was 
as follows : 
Before immersion, the piece of wood weighed - 207 grains* 
After the experiment, - - - 315 
Quantity of water absorbed, - - 108 
Weight in the air after immersion, - 315 grains. 
Weight of the plug in fresh-water, (temp. 40°), - 214 
Weight of an equal bulk of water, - - 2934 grains. 
Hence, specific gravity of the wood, after immersion, 1.073. 
As I apprehended that the portion of the plug through which 
the water had made its way into the bottle, would be more im- 
pregnated than the rest, from the expulsion of the air into the 
bottle, i cut away the projecting sides and corners, and formed 
the central pal*t into a cylinder. But the specific gravity of this 
was less than that of the whole, being only 1.032 ; and the ex- 
tremity that was in the bottle was lightest of all. This effect I 
attributed to the want of expansion in this part, occasioned by 
the strength of the ring of the bottle by which it was compress- 
ed, thus preventing it on the lower part from receiving its due 
share of moisture. On splitting the wood, it was found to be 
wet throughout its substance. 
I next attempted the filtration of water through the pores of 
a cylindrical piece of mahogany 4| inches in length. In this 
experiment, I employed a strong oblong vessel of copper, kindly 
furnished me by Captain Manby, (who, with his usual public 
spirit, accompanied me on the voyage, with a view of trying an 
apparatus for increasing the facilities and diminishing the dan- 
gers of capturing the whale). This vessel, with the mahogany 
screwed into the neck, was sent to the bottom, where the depth 
was 5040 feet, and allowed to remain an hour and a half. But 
the enormous pressure to which it was subjected, being about 
fifty tons, (a ton per square inch), crushed the vessel, though 
every part was an arch, into an irregular flat form, and tore the 
