The Survey of British Lakes
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Scottish Geographical Magazine ISSN: 0036-9225 (Print) (Online) Journal homepage: http://www.tandfonline.com/loi/rsgj19 The Survey of British lakes James Chumley To cite this article: James Chumley (1902) The Survey of British lakes, Scottish Geographical Magazine, 18:8, 413-422, DOI: 10.1080/00369220208733376 To link to this article: http://dx.doi.org/10.1080/00369220208733376 Published online: 27 Feb 2008. Submit your article to this journal Article views: 6 View related articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=rsgj20 Download by: [University of California, San Diego] Date: 28 June 2016, At: 16:53 A NOTE UPON THE METHODS OF BOTANICAL GEOGRAPHY. 413 (6) J. F. Schouv, Grundziiye einer allgemeinen Pflanzengeographie. Berlin, 1823. (7) .Dr. Eugen Warming, Lehrluch der Ohologischen Pflanzengeographie. Copenhagen, 1896. (8) H. 0. Watson, The Geographical Distribution of British Plants. Third edition, 1843. (9) Moritz Willkomm, Grundzitge d. Pflanzenverhreitung auf der iberischen Halbinsel. Leipzig, 1896. THE SUEVEY OF BRITISH LAKES. By JAMES CHUMLEY, of the Challenger Expedition Office, Edinburgh. As indicated in a previous number of the Scottish Geographical Magazine, the systematic work of the Lake Survey was started early in April last, and has since been carried on uninterruptedly under the personal super- intendence of Sir John Murray, K.C.B. From Eannoch Lodge, where Sir John Murray and his family took up their residence towards the end of March, excursions were made to the lakes in the neighbourhood, and we are enabled to report that most satisfactory progress has been made. At the time of writing twenty-two lakes had been completely surveyed, viz., Lochs Earn, Tay, Tummel, Eannoch, Lochan Sr6n Smeur, Eigheach, Laidon, Ba, Lochan na h-Achlaise, Lochan na Stainge, Buidhe, Lyon, Iubhair, and Dochart, in the basin of the Tay; Lochs Laggan, Lochan na h-Earba, Treig, Ossian, and Ghuilbinn, in the basin of the Spean; Loch Tulla flowing into Loch Awe, Loch Arkaig flowing into Loch Lochy, and Loch Crunachan flowing into the Spey. Lochs Morar, Shiel, and Eilt have since been surveyed, and the staff are now engaged on the surveys of Loch Maree and neighbouring lochs. In carrying out this work Sir John Murray has had the continuous assistance of Mr. T. N. Johnston, M.B., CM., and Mr. James Parsons, B.Sc, and for several weeks he was assisted by Mr. E. M. Clark, B.Sc. In the surveys of Lochs Ossian and Ghuilbinn he had also the assistance of Dr. J. Sutherland Black, M.A.; in the survey of Loch Laggan he was assisted by Sir John Jackson, and in the surveys of Lochs Tulla and Tummel he was assisted by Mr. D. C. M'Intosh, M.A. Mr. James Murray joined the survey in the end of April, and Mr. J. Hewitt and Mr. T. E. H. Garrett, of Jesus College, Cambridge, in the middle of June, Downloaded by [University of California, San Diego] at 16:53 28 June 2016 while Mr. D. J. Scourfield has been studying the Entomostraca of the lakes during the past few weeks. In order to facilitate the progress of the survey in every way, Sir John Murray has added to his resources a motor car, specially built for him by the Albion Motor Car Co., Glasgow, and an experienced driver, Mr. Thomas Hardie, was engaged some weeks . ago; the surveying staff will thus be enabled to proceed from one lake to another with the least possible delay. The circumstances which led up to the present work of the Lake . Survey are well known to the readers of the Scottish Geographical Magazine. A few years ago Sir John Murray and the late Mr. Fred. P. Pullar 414 SCOTTISH GEOGRAPHICAL MAGAZINE. undertook jointly to carry out a systematic bathymetrical and physical survey of the fresh-water lochs of Scotland, and they commenced -with those lying in the basin of the Forth. The first part of their report, dealing with Lochs Katrine, Arklet, Achray, Vennacher, Drunkie, Lubnaig, Voil, and Doine, was published in vol. xvi. p. 193 ; the second part, dealing with Lochs Chon, Ard, Menteith, and Leven, in vol.- xvii. p. 113; and the third part, dealing with Lochs Ericht and Garry in the basin of the Tay, in vol. xvii. p. 169. Just after this third part had been prepared for publication the work was unfortunately brought to a standstill by the accidental death of the late Mr. F. P. Pullar, who sacrificed his life in a gallant attempt to save others (see obituary notice, vol. xvii. p. 148). As a memorial to this talented young author, his father, Mr. Laurence Pullar, and his collaborator, Sir John Murray, decided that the work in which he took such interest should be completed at their joint expense. Only four of the lakes recently surveyed by the Lake Survey had, as far as we are aware, been previously systematically sounded, viz., Lochs Tay, Earn, Eannoch, and Tummel, which were surveyed by Mr. Grant Wilson of the Geological Survey of Scotland, in 1888 (see vol. iv. p. 251); Loch Earn was again sounded by Sir John Murray and the late Mr. Pullar in 1900, though the results were not published. Mr. "Wilson's soundings agree, on the whole, with those of the Lake Survey, the differences observed being probably due to a difference in the level of the surface waters at the time the surveys were made. For instance, the maximum depth observed by the Lake Survey in Loch Tay was 508 feet, whereas Mr. Wilson records a depth of 85 fathoms, or 510 feet; in Loch Earn the maximum depth observed by the Lake Survey was 287 feet, while Mr. Wilson records 48 fathoms, or 288 feet; in Loch Tummel the maximum depth observed by the Lake Survey was 128 feet, while Mr. "Wilson records 20-f fathoms, or 124 feet. The methods and apparatus employed by the Lake Survey are the same as those used by Sir John Murray and the late Mr. F. P. Pullar, which were fully described in the first part of their report, and need not be repeated here, but special attention is now paid to the deter- mination of the level of the surface of each lake above the level of the sea at the time the survey is being carried out, so that the true relation between the contour-lines above and below the water-level may.be accurately known. Before sounding out a lake a horizontal line is painted, if possible on some convenient rock-surface, Downloaded by [University of California, San Diego] at 16:53 28 June 2016 one, two, or three feet above the surface of the water, thus: L j —S the figure above the horizontal line indicating the height in feet of that line above the level of the water. The height above sea-level is then care- fully determined by levelling with a dumpy level to the nearest Ordnance . Survey bench-mark. Each day the level of the water is compared with the Lake Survey level-mark, and any change noted, for sometimes the water of the lake may rise or fall while the survey is in progress. In Loch Treig, for instance, the water rose to the extent of a foot during THE SURVEY OF BRITISH LAKES. 415 the time devoted to the survey, and the earlier soundings had to be corrected accordingly. An interesting point in connection with the work of the Lake Survey is the record, probably for the first time in Scotland, of " seiches " in some of the larger lakes. A short note on one of these examples of rhythmic pulsation in the waters of a lake has been contributed by Mr. Parsons in a recent issue of Nature (see Nature, No. 1702, June 12, 1902, p. 162). Professor Forel believes that these pulsations are due to variations in barometric pressure, while they have been attributed by others to wind-velocity or to earth-movements. No continuous observa- tions on this novel phenomenon have yet been made by the Lake Survey, but in the course of a few weeks a " limnograph," which has been con- structed in Geneva under the supervision of Dr. Ed. Sarasin, will be set up on the margin of one of the lakes, for the purpose of giving a continuous record of the variations in the level of the surface waters of the lake. The thanks of the staff of the Lake Survey are due to Sir Eobert Menzies, Sir John Stirling Maxwell, Lochiel of Achnacarry Castle, Sir John Eamsden, and other Highland proprietors, for valuable assistance rendered during the recent surveys. Some of the maps of the lakes recently surveyed are now sufficiently far advanced to enable us to offer a few preliminary remarks regarding their depth and conformation, which may be interesting to readers of the Scottish Geographical Magazine. The large figures giving the cubic mass of water in each lake are difficult to grasp, arid, with the view of rendering them more intelligible, we have in each case indicated the dimensions of an imaginary cubical reservoir, into which the waters from each loch may be supposed to be run off. LOCH TAY. Loch Tay may fairly claim to be the largest lake in the basin of the Tay, though Loch Ericht is quite comparable as regards length, maximum breadth, and maximum depth, but the average breadth of Loch Tay is greater than that of Loch Ericht. Its superficial area is therefore larger, its mean depth is greater, and it holds a larger cubic mass of water.