274 SIR RODERICK I. MURCHISON'S ADDRESS. [May 23, 1859. 



tlie Lords Commissioners of the Admiralty lias been officially com- 

 municated to Mr. Evans for the labour and scientific skill he has 

 bestowed upon this beautiful and useful production. 



Besides the surveys above enumerated as in progress in different 

 parts of the world, the labours of the Hydrographic Office during 

 the past year have consisted in the publication of upwards of 80 

 new and corrected charts of various coasts and plans of harbours. 

 It may enable my hearers to form some idea of the activity that 

 prevails in this department if I mention a fact just made known to 

 me — that during this very month of May the large number of 

 20,000 Admiralty Charts have been printed and the greater part 

 sold to the public. In addition to these works the usual annual 

 lists of lights, of notices to mariners, of tide-tables, have been pub- 

 lished ; and lastly I may conclude this portion of my Address with an 

 announcement which cannot but deeply interest all geographers, 

 namely, that it has been determined that the Table of Maritime 

 Positions, giving the latitude and longitude of 8000 places on the 

 globe, compiled with great care by our late lamented Member 

 Henry Raper, shall be annually corrected and kept on a par with the 

 latest information at the Admiralty, as the best tribute that hydro- 

 graphy can offer to the memory of our deeply regretted friend and 

 medallist. 



Land Surveys. 



Ordnance Survey. — The reduction of plans on larger scales to the 

 size of maps by means of photography has been brought into 

 efficient public practice by Colonel James, the able Superintendent of 

 the Ordnance Survey Office and Topographical Department, and a 

 report of a committee, appointed by the Secretary of State for War, 

 of which I was the Chairman, has entirely approved of the process. 



When it is known that the largest of the British surveys as now 

 sanctioned are on the scale of 25*344 inches to a mile, or the scale 

 of one square inch to one acre, and that the expense of reducing 

 that enormous scale down to six inch and one inch scales by means 

 of any mechanical contrivance such as a pentagraph must be very- 

 considerable, the employment of photography to effect this purpose 

 rapidly, accurately, and economically, reflects the highest credit on 

 Colonel James. 



A full and detailed account of the progress of the Ordnance 

 Survey of the British Isles, and of the preparation of the plans and 

 maps upon four different scales, will be found in the last Report 



