May 26, 1856.] ADMIRALTY SURVEYS. ' 137 



tho whole of Scotland will bo finished, as well as the north of 

 England, within ten years. 



The system of registering the levels by means of horizontal con- 

 tours, has been for some time generally adopted on the Ordnance 

 Survey, and their great value is now very generally acknowledged. 

 The contours, when reduced to the one-inch scale, form the most 

 perfect basis for the hill-sketching ; and the plans now produced are 

 the most perfect in all respects which were ever made. In England, 

 the counties of Ijancaster, York, and Durham have been surveyed 

 for the large scales. In Scotland, the shires of Wigton, Kirkcud- 

 bright, Edinburgh, Haddington, Linlithgow, Fife, Kinross, Ayr, 

 Dumfries, Peebles, with the Isle of Lewis, have been survej^ed. 

 Eight of the above counties have already been published, and the 

 remainder are in course of publication, whilst the survey is now 

 proceeding in Berwick, Lanark, Roxburgh, and Selkiik-shires. 



The one-inch general Map proceeds pari passu with the surveys 

 on the larger scales. 



The whole of Ireland has been published on the 6-inch scale, and 

 the 1-inch map is rapidly progressing, and several of the sheets are 

 published. 



While the subject of our Trigonometrical Surveys is under con- 

 sideration, I may mention, on tho authority of Col. James, that tho 

 Surveys of our Colonies are proceeding in the following places, 

 under officers of the Eoyal Engineers, having, in most places, men 

 of the Royal Sappers and Miners under them : — Australia, Tasmania, 

 Ceylon, Mauritius. 



Admiralty Surveys. — To a maritime nation like Great Britain, tho 

 importance of detailed nautical charts, with ample sailing direc- 

 tions for the guidance of the mariner, is too obvious to render any 

 excuse necessary for entering with some minuteness into the state 

 of the sui-vey of our own shores. A rapid reconnaissance of a coast 

 might have been tolerated half a century ago ; but such a sui-i^ey of 

 any shore, much less of our own shores, cannot now be accepted. 

 The Ordnance large-scale survey, with its almost mathematical 

 exactness (within certain limits), and the labours of the civil 

 engineer, with his accurate lines of levels extending across tho 

 island from sea to sea, have shown us that greater accuracy in 

 our coast surveys has become requisite. Hence the necessity, 

 among other considerations, of determining the tide levels with 

 the greatest care in our estuaries and rivers. This has lately 



