May 24, 1858.] 
ADMIRALTY - SURVEYS— ENGLAND. 
259 
Europe, while it is separated from Norway and Sweden by a gulf 
or fiord some hundred fathoms in depth. Probably it may not be 
generally known that some of the deep wells in London and Sheer- 
ness draw their fresh water from a stratum which lies fully 300 feet 
below the level of the bottom of any portion of the North Sea that 
intervenes between this island and the coasts of Belgium, Holland, 
or Denmark. The physical geographer will therefore find, if he ex- 
amines them, that nautical charts teach something more than the 
mere depth sufficient for the wants of navigation. This undoubtedly 
is their first and main use ; but in the course of a rapid summary 
of their labours during the past year, I shall be enabled to show you 
that the Admiralty Surveyors have sounded hitherto unfathomed 
depths both in the North and South Atlantic, in the Indian Ocean, 
and in the Red Sea, and have brought up sufficient of the bottom to 
enable geologists to explain the structure of new continents, now 
forming at a depth of 2000 fathoms below the surface of the water. 
England . — The re-examination of the river Thames, to which I 
referred last year, under Commanders Burstal and Cudlip, has been 
completed from Putney to Woolwich, and laid down upon the large 
scale Ordnance plans of 60 inches to a statute mile — a minute and 
careful survey, which will form a valuable standard for reference 
hereafter, when the labours of the Thames Conservancy Board shall 
have dredged a deep, uniform channel, navigable at low water up 
to the London Pool. The deepening of the bed of the river, conse- 
quent upon the removal of old London Bridge in the year 1832, 
has been striking, and holds out encouragement to reconstruct the 
old-fashioned bridges at Newcastle, Wexford, and Cork, which now 
act as dams in their respective rivers, as the Tyne, the Slaney, and 
the Lee. 
On the east coast of England the chief topographical changes 
consist in the improvement of the entrances of the several tidal 
harbours. The channel of the Tees has been dredged and trained 
to a fair curve, which can hardly fail to deepen itself. A chart of 
Tees Bay, on the scale of 3 inches to a mile, has recently been pub- 
lished at the Admiralty. It includes Hartlepool and Pedcar, and 
thus shows at one view all the sites that have been recommended 
in this immediate locality for a harbour of refuge — an imperative 
work that can no longer be delayed, when we look at the fearful 
loss of life from wreck that annually occurs on this coast. At the 
entrance of the Tyne large works are in progress, which we trust 
may do somewhat to improve the mouth of that important river, in 
