176 REAR-ADMIRAL F. W. BEECHEY'S ADDRESS. [May 26, 1856. 



taining the eastern frontier of the Cape of Good Hope, drawn 

 by Mr. Henry Hall, of the Ordnance department in that colony, 

 whose merits as a cartographer are well known. This map appears 

 very opportunely, as it includes the country of the Bassutos, where 

 disturbances are apprehended. Mr. Stanford has also presented a 

 copy of the new edition of Baily's Map of Central America, with 

 corrections from the recent surveys of Squier, Codazzi, and others. 



Capt. Burton has completed the narrative of his dangerous journey 

 to Mecca and Medina, in the disguise of an Affghan pilgrim ; and he 

 has also published an account of his visit to the African city of 

 Harar, which had been deemed inaccessible, owing to the savage 

 and hostile character of the chief, as well as of the people. 



Our associate. Captain Charles F. A. Shadwell, r.n., c.b., has added 

 to his useful publications on navigation a case containing, on a 

 dozen cards, 'Formulas of Navigation and Nautical Astronomy;' 

 also another work on the Management of Chronometers. 



The labours of other Members have been alluded to in various 

 parts of this Address in connection with the different countries to 

 which they relate. 



Physical Geography. 



During the past year there has appeared, under the direction of 

 the zealous superintendent of the Ordnance Survey, an abstract 

 of the operations, carried on in Ireland, for the purpose of re- 

 ferring the mean water levels upon various parts of the coast to 

 a common standard. Although these observations have long been 

 discussed by our Astronomer Eoyal, and will be found in the 

 Transactions of the Eoyal Society, yet it is only now that the com- 

 plete details of the operations have been published ; and as the 

 observations present this curious result, viz. that the mean sea level 

 is higher upon the northern part of Ireland than upon the southern 

 part, and as no notice of this has ever appeared in our Journal that 

 I am aware of, I take this occasion of observing that, if we take as 

 the standard Courtown, in Wicklow — a spot remarkable as having 

 no perceptible rise or fall of its tide, and about midway on the axis 

 of the great tidal wave between the extremities of Ireland — we shall 

 find that the mean sea level stands higher on the north of Ireland 

 (Ballycastle) by 0-881 feet and lower on the south (Castle Townsend) • 

 by 0-938 feet than it does at Courtown. I know it will be interest- 

 ing to many of our Associates to have these facts inserted in their 

 Journal. 



