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1.
《测量评论》2013,45(12):329-330
AbstractMajor Hotine (E.S.R., No. II, pp. 264–8) still finds the location of a reference spheroid to offer insuperable difficulties. I confess that my difficulty is to see his! In my previous article (E.S.R., No. 8) at the foot of page 76, I used the word “coincidence” in error for “parallelism”. This harmonizes the article and I am glad that Major Hotine has directed attention to the error. 相似文献
2.
《测量评论》2013,45(8):73-78
Abstract1. The object of this note is to clear up what I believe to be some misconceptions regarding the use of a reference system by a surveyor of the earth's surface. In his article “An Aspect of Attraction”, E.S.R., No. 7, pp. 24–8, Major M. Hotine expressed doubts as to the validity of the process usually followed. I may say at once that I consider these doubts are unfounded. 相似文献
3.
《测量评论》2013,45(12):345-346
AbstractIn the course of his stimulating and suggestive paper in your recent issue, No. ro, pp. 226–38, Mr. A. J. Potter writes on p. 233 “but there is no simple construction by which X can then be found”, and again on p. 237 “a direct construction, if there be such”. This cheerful challenge invites the construction of a circle centred on a given line, passing through a given point thereon, and touching a given circle, and I have found the lure of Mr. Potter's gauntlet as irresistible as its recovery has proved delicate. In order to shoulder responsibility and by no means to claim highly improbable originality, let me confess that the problem is new to me and the two constructions I offer are my own; I venture to hope that Mr. Potter may consider one or other of them not unworthy of his epithet “simple”, though I freely admit the aptitude of his empiric procedure to its purpose. The proofs are not long, but for fear of overshooting my welcome I offer them to anyone for the asking; and for the same reason my diagrams are small and therefore mere. 相似文献
4.
《测量评论》2013,45(13):386-391
Abstract The International Population Union.—In 1927, as President of the Geographical Association, it was my duty to deliver an address to the Association. I chose as my subject “Population and Migration” with special reference to the English-speaking peoples. One result of the publication of this in Geography, the journal of the Association, was that I was invited to attend the World Population Conference, which was held at Geneva in August-September 1927. The Conference was a very interesting affair. It was organized, and largely paid for, by Mrs. Margaret Sanger. About twenty-four countries were represented. The late Sir Bernard Mallet presided, and in one of his speeches, winding up the Conference, he truly said that we might “congratulate ourselves on having shown the world that population questions, which bristle with controversy, political, moral, and religious, can be discussed by sensible people without animosity or unseemly wrangling”. 相似文献
5.
AbstractThe majority of readers are doubtless aware of the masterly summary of the “History of the Calendar,” written for the Nautical Almanac for 193I (pp. 734–747) by Dr. J. K. Fotheringham. Most are probably also aware that the question of Calendar Reform has been considered by the League of Nations. At the Conference on Communications and Transit of 1931, October 19, the League adopted a resolution recommending a fixed Easter, but declared that “the present time is not favourable … for considering … a reform of the Gregorian calendar.” For information on the various measures of reform proposed at Geneva the works noted below may be consulted. In the meantime, pending the coming of reform—for come it will—readers may desire to.have a summary history of the question, with a statement of a solution which is of somewhat the same nature as others which have been proposed. 相似文献
6.
AbstractI. Introduction.—Map projection is a branch of applied mathematics which owes much to J. H. Lambert (v. this Review, i, 2, 91). In his “Beyträge zum Gebrauche der Mathematik und deren Anwendung” (Berlin, 1772) he arrived at a form of projection whereof the Transverse Mercator is a special case, and pointed out that this special case is adapted to a country of great extent in latitude but of small longitudinal width. Germain (“Traité des Projections”, Paris, 1865) described it as the Projection cylindrique orthomorphe de Lambert, but he also introduced the name Projection de Mercator transverse or renversée; he shows that Lambert's treatment of the projection was remarkably simple. 相似文献
7.
《测量评论》2013,45(61):267-271
AbstractSome publications that have dealt with the question of convergence of meridians seem, to the present writer, to be clouded with misconception, and these notes are intended to clarify some points of apparent obscurity. For instance, A. E. Young, in “Some Investigations in the Theory of Map Projections”, I920, devoted a short chapter to the subject, and appeared surprised to find that the convergence on the Transverse Mercator projection differs from the spheroidal convergence; the explanation which he advanced can be shown to be faulty. Captain G. T. McCaw, in E.S.R., v, 35, 285, derived an expression for the Transverse Mercator convergence which is equal to the spheroidal convergence, and described this as “a result which might be expected in an orthomorphic system”. Perhaps McCaw did not intend his remark to be so interpreted, but it seems to imply that the convergence on any orthomorphic projection should be equal to the spheroidal convergence, and it is easily demonstrated that this is not so. Also, in the second edition of “Survey Computations” there is given a formula for the convergence on the Cassini projection which is identical, as far as it goes, with that given for the Transverse Mercator, while the Cassini convergence as given by Young is actually the spheroidal convergence. Obviously, there is some confusion somewhere, and it is small wonder that Young prefaced his remarks with the admission that the subject had always presented some difficulty to him. 相似文献
8.
《测量评论》2013,45(53):276-278
AbstractI Have read with interest Mr. L. P. Lee's remarkably well-informed article in the January number (vii, 51, 190) on “The Nomenclature and Classification of Map Projections”. I agree with much of what Mr. Lee says, but I cannot think that he has always been happy in his choice of names. 相似文献
9.
《测量评论》2013,45(43):274-284
AbstractRecently the writer of this article became interested in the conical orthomorphic projection and wanted to see a simple proof of the formula for the modified meridian distance for the projection on the sphere. Owing to the exigencies of the war, however, he has been separated from the bulk of his books, and, consequently, has had to evolve a proof for himself. Later, this proof was shown to a friend who told him that he had some memory of a mistake in the sign of the spheroidal term in m4given in “Survey Computations”, perhaps the first edition. Curiosity therefore suggested an attempt to verify this sign, which meant extending his work to the spheroid. This has now been done, with the result that the formula given in “Survey Computations”, up to the terms of the fourth order at any rate, is found correct after all. 相似文献
10.
《测量评论》2013,45(12):352-357
Abstract Preliminary Note.—The substance of this article was written in 1921 at the request of Lieut-Col. Wolff, who was then in charge of the Levelling Division of the Ordnance Survey and with whom the author collaborated in writing “The Second Geodetic Levelling of England and Wales, 1912–21” under the direction of Sir Charles Close. It was not intended for publication and was not again considered until 1928, when a discussion by correspondence was started by the Surveyor-General of Ceylon on the subject of hill circuits in levelling. In this discussion the survey authorities in Great Britain, Canada, India, and South Africa took part, but the main theme was the accumulation of error due to the large number of sightings necessary in hilly country and the question whether a common formula for such country and for flat country was justifiable. In his contribution Dr. van der Sterr made a brief allusion to the subject of the present paper and Dr. de Graaff Hunter went into details. His contribution and the following remarks therefore have some arguments in common. 相似文献
11.
《测量评论》2013,45(29):413-417
AbstractIn the E.S.R. No. 17 of July 1935, page 138, there appeared an article by Prof. F. A. Redmond on “The use of Even Angles in Stadia Surveying”. Since I have given this method a six-months' test in the field, using Prof. Redmond's “Tacheometric Tables” for the reduction of the measurements, the conclusions reached may be of some interest. 相似文献
12.
《测量评论》2013,45(31):38-50
AbstractOn page 480 of the last number of this Review Capt. E. H. Thompson, R.E., in his paper on “The Condition for the Construction of a Conformal Projection”, deals with a subject which, in the opinion of the present writer, is rather insufficiently explained or dealt with in any text-book on Geodesy or on Map. Projections that he has seen. The explanations or proofs usually given are probably adequate if it can be assumed that the reader has a fairly good knowledge of the properties of functions of the complex variable. 相似文献
13.
《测量评论》2013,45(7):7-12
AbstractIn his article “Standards of Length in Question” published in the last number of this Review (Vol. i, pp. 277–-84) Captain G. T. McCawgave us most interesting and valuable history concerning the questionable past of the international metre. He has, it may be assumed, exhausted published evidence; but he states that he can find no reference to invitations from this country to France and Holland to send their fundamental standards for comparison with others at the Ordnance Survey in the eighteen sixties. 相似文献
14.
《测量评论》2013,45(80):60-65
AbstractThe 200th anniversary of the publication by Murdoch Mackenzie (Senior) in May 1750 of his “Orcades, or a Geographic and Hydrographic Survey of the Orkney and Lewis Islands, in 8 maps”, is an opportune moment for a brief résumé of the contribution made by Mackenzie and his successors in the field of nautical surveying. The appearance of this work ushered in a new era in marine survey, for it was the first charting carried out in this country based on a rigid triangulation framework. The importance of this fact can further be appreciated when it is remembered that a contemporary topographic map like General Roys' famous “Map of the Highlands” begun in 1747 was little more than an elaborate compass sketch; thus under Mackenzie's influence, marine surveying at this period was ahead of its topographic counterpart. 相似文献
15.
《测量评论》2013,45(41):151-154
AbstractIn the July 1940 issue of the Empire Survey Review Mr A. V. Lawes contributes a valuable article, “The Application of the Gauss Method of Collimation to the Adjustment of Survey Instruments”. One section of the article describes four methods of adjusting collimators at solar focus, in other words of assuring that the emitted rays are parallel or that the target appears at an infinite distance. Mr Lawes rightly claims that auto-collimation is the most accurate of the four methods, and he warns readers that “the reflector used in this method must be as perfect optically as the objective”. However, he fails to give any method of testing the result obtained by following his directions, and experience suggests that auto-collimation may give a result considerably in error even though the reflector may with some justification be presumed to be good. 相似文献
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17.
《测量评论》2013,45(58):142-152
AbstractIn January 1940, in a paper entitled “The Transverse Mercator Projection: A Critical Examination” (E.S.R., v, 35, 285), the late Captain G. T. McCaw obtained expressions for the co-ordinates of a point on the Transverse Mercator projection of the spheroid which appeared to cast suspicion on the results originally derived by Gauss. McCaw considered, in fact, that his expressions gave the true measures of the co-ordinates, and that the Gauss method contained some invalidity. He requested readers to report any flaw that might be discovered in his work, but apparently no such flaw had been detected at the time of his death. It can be shown, however, that the invalidities are in McCaw's methods, and there seems no reason for doubting the results derived by the Gauss method. 相似文献
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19.
《测量评论》2013,45(3):100-109
AbstractWILLEBRORD SNEL VAN ROIEN, the “learned Snellius,” was born in 1580 at Leyden, where his father Rudolf was Professor of Science. He naturally proceeded to the university, and made such rapid progress under his tutor, L. van Ceulen, that he was already in 1600 delivering lectures on Ptolemy's “Almagest.” With his mind developed by travel in Europe, including a residence of some duration at Prague, where he was associated with Tycho Brahe before that great observer's death in 1601 and with the still more eminent Kepler as another of Brahe's pupils, he had acquired such scholarship as to publish in 1608 a daring reconstruction of the defective work, “De sectione determinata,” by Apollonius of Tyana. This was the year of his marriage to Maria de Lange, daughter of the Burgomaster of Schoon. 相似文献
20.
《测量评论》2013,45(74):155-161
Abstract60. The three standard or field reference tapes are stored at the N.P.L., Teddington, and standardised to class “A” accuracy immediately before and after each base measurement. In order to reduce the residual contraction or “creep” of in var when exposed to higher temperatures, the tapes are retained for as short a time as possible in the Sudan and since 1945 they have been transported in both directions by air. In this way, any “creep” should be revealed by the standardisation after a measurement. From the formula of Dr. Guillaume the ultimate shortening, in the temperatures prevailing at Meheisa and Husheib, would have been ?26 and ?20 × 10?5 ft. respectively and it is clear from Table 3 that this tiresome source of uncertainty is largely eliminated by the procedure adopted. 相似文献