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1.
《测量评论》2013,45(70):330-344
AbstractThe late war has been responsible for many unusual situations—not the least of which was that of certain British Colonial Surv1ey Offices passing under the control of an Asiatic Invader, and it is thought that the story of one of them—the Survey Department of Malaya—will not be without interest to readers of this Review. 相似文献
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《测量评论》2013,45(44):334-338
AbstractThe method of Garavito, Director of the Observatory of Bogota, consists in choosing two stars, one to the north of the zenith, the other to the south, such that the algebraical half-sum of their declinations may not differ much—at the limit 15′ or 20′—from the latitude of the place. As a matter of fact the difference may be slightly greater without inconvenience. 相似文献
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none 《The Cartographic journal》2013,50(2):123-145
AbstractIn their pre-war heyday Batholomew, that most famous of British commercial mapmakers, had a huge worldwide business in every sort and scale of map and atlas for every purpose; not to mention, at one time, an extensive general printing trade. But, even so, their name became firmly associated in the public consciousness with one particular design of map on one particular scale — the half-inch to one mile (1.126 720) layer colored map of Great Britain. This study deals with the early history of the phenomenon, in the context of the firm's other work. It concludes with the completion of the England and Wales series, and the moment when it could be said, in the most elevated and objective of contexts, that the British map buyer — trade and public both — had, thanks to this map, acquired 'the Bartholomew habit'. 相似文献
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Abstract19. Formulae.—In Nos. 6, vol. i, and 9, vol. ii, pp. 259 and 156, there has been described a new method for dealing with long geodesics on the earth's surface. There the so-called “inverse” problem has claimed first attention: given the latitudes and longitudes of the extremities of a geodesic, to find its length and terminal azimuths. It remains to discuss the “direct” problem : a geodesic of given length starts on a given azimuth from a station of known latitude and longitude; to find the latitude and longitude of its extremity and the azimuth thereat. The solution of this direct problem demands a certain recasting of the formulae previously given. In order of working the several expressions now assume the forms below. 相似文献
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Abstract1. Some Preliminary Considerations.—Let it be supposed that an iceberg is captured by an ice-field. It will be assumed that the field can be packed, either by opposing currents or by pressure against a land mass on one side. Compared with the vertical dimension of the berg the thickness of the field will be comparatively small. 相似文献
6.
《测量评论》2013,45(20):354-358
Abstract 6. Further Expansions.—Equations (4.3) and (5.5) enable a computer to transform coordinates from the Cassini projection to the Gauss projection without recourse to geographical coordinates. If applied to one or two points, no doubt these equations would be quite satisfactory; but if applied to 100,000 points their use would be laborious and it would be difficult to adapt them to machine computing. 相似文献
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AbstractIt generally happens that, when trade is bad and there is a sharp drop in the revenue of a country such as to necessitate immediate economy, one of the first of the public services to be affected is survey; and, of all the different branches of surveying, the one that suffers most is usually the trigonometrical surveyor its equivalent. This is in spite of the fact that, taking the long view, the tdgonometrical survey is perhaps the most fundamental of all. The trouble is, of course, that it is very difficult for the non-technical individual or official to appreciate the importance of the work—indeed, it is doubtful if all surveyors realise this. 相似文献
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《测量评论》2013,45(14):472-484
Abstract Choice of Beacon.—The general question as to whether luminous or opaque signals should be used in ruling triangulation has recently been discussed in the Empire Survey Review (No.9, pp. 151–2 and No. 12, pp. 335–6). It may here be summarized that opaque beacons of suitable design are sufficiently accurate and offer the considerable advantages of being immediately available for subsequent work, of requiring little or no attention, and of being visible from all directions without rearrangement. Moreover, if of the tripod or quadripod type, they need not be dismounted during occupation of the station for observing, so that 0bservations by more than one observer are not interrupted. The only occasion for using luminous beacons arises from bad visibility, whether through atmospheric haze or lack of a suitable background or through the economic necessity of completing observations at night. These conditions are not peculiar to ruling triangulation. An ”all-round” type of luminous beacon—a pressure oil lamp or a rotating mirror system—can be used for nightwork or against a dark background, but single-direction luminous beacons are necessary to overcome haze. 相似文献
11.
《测量评论》2013,45(11):258-264
Abstract The Ordnance Survey and the War.—I shall not inflict upon the readers of this Review any very long account of the work of the Ordnance Survey during the Great War. At that time the work of the Survey suffered from one necessary disadvantage: all the young men on its establishment, whether in the R.E. Companies or on the Civil Staff, left for active service. As a slight compensation for this inevitable dislocation all money difficulties in the preparation of maps for war disappeared. 相似文献
12.
Summary Within potential theory of Poisson-Laplace equation the boundary value problem of physical geodesy is classified asfree andnonlinear. For solving this typical nonlinear boundary value problem four different types of nonlinear integral equations corresponding
to singular density distributions within single and double layer are presented. The characteristic problem of free boundaries,
theproblem of free surface integrals, is exactly solved bymetric continuation. Even in thelinear approximation of fundamental relations of physical geodesy the basic integral equations becomenonlinear because of the special features of free surface integrals. 相似文献
13.
《测量评论》2013,45(32):67-85
Abstract Introduction.—Although much has been written on the various branches of surveying, few text-books do more than give the problem of Map Maintenance a passing mention. It is true that probably the major problem of the surveyor, when considering the world as a whole, is the urgent need of any sort of accurate map for most of its surface, yet at the same time quite considerable areas have already been surveyed, and the maintenance of these areas forms a very formidable problem in itself. Moreover, it is not generally realized that problems of maintenance necessitate a complete reorientation of technical outlook in comparison with questions of an initial survey. Clearly, when maps are being made in the first instance, the primary requirement is an adequate framework, whose main essentials are accuracy; rigidity and permanence. The filling in of the topographical detail and the final reproduction are matters of necessarily secondary importance. Furthermore, as the time required for the field work is large in comparison with the office stages, there is little actual or apparent gain in reducing the time taken on drawing and reproduction. In these circumstances the problem of an initial survey is essentially mathematical in its technique, little attention being required for the final stages of drawing and reproduction, which can be carried out, by craftsmen, at the unhurried pace which it has been their privilege to maintain in the past. 相似文献
14.
《测量评论》2013,45(77):302-306
AbstractAlthough during World War II field work on geodetic subjects other than those directly connected with the war effort remained practically in abeyance, the war provided unique opportunities for the study and execution of several interesting problems such as the linking of Indian triangulation with Iraq and Iran on the one hand and Siam and Malaya on the other. A detailed account of the Geodetic work of the Survey of India during the period 1939-47 is given in the Survey of India “Technical Report 1947—Part III, Geodetic Work”. 相似文献
15.
《测量评论》2013,45(37):398-409
AbstractDid you ever ask yourself the question, “What are the personal reactions of research workers before, during and after a successfully completed investigation?” For instance—what were the feelings of the discoverers of insulin, of early maturing Marquis wheat; what were the reactions of those who conceived and built the Quebec bridge, of those who perfected the application of aerial photography to mapping and other sciences ; what were the emotions of those who conceived the echo-sounding machine, of such advantage to the operations of hydrographers and mariners? The answer to one such question is the subject of this paper. 相似文献
16.
Abstract Introductory Remarks.—A line of constant bearing was known as a Rhumb line. Later Snel invented the name Loxodrome for the same line. The drawing of this line on a curvilinear graticule was naturally difficult and attempts at graphical working in the chart-house were not very successfuL Consequently, according to Germain, in 1318 Petrus Vesconte de Janua devised the Plate Carree projection (“Plane” Chart). This had a rectilinear graticule and parallel meridians, and distances on the meridians were made true. The projection gave a rectilinear rhumb line; but the bearing of this rhumb line was in general far from true and the representation of the earth's surface was greatly distorted in high latitudes. For the former reason it offered no real solution of the problem of the navigator, who required a chart on which any straight line would be a line not alone of constant bearing but also of true bearing; the first condition necessarily postulated a chart with rectilinear meridians, since a meridian is itself a rhumb line, and for the same reason it postulated rectilinear parallels. It follows, therefore, that the meridians also must be parallel inter se, like the parallels of latitude. The remaining desideratum—that for a true bearing—was attained in I569 by Gerhard Kramer, usually known by his Latin name of Mercator, in early life a pupil of Gemma Frisius of Louvain, who was the first to teach triangulation as a means for surveying a country. Let us consider, then, that a chart is required to show a straight line as a rhumb line of true bearing and let us consider the Mercator projection from this point of view. 相似文献
17.
《测量评论》2013,45(63):20-24
AbstractThe shutter eyepiece is a device for eliminating the effects of personality in observations involving the timing of a moving star crossing graticule lines. It is of importance in longitude observations and in any mixed observations involving timing of star passages over cross-lines—vertical, horizontal or oblique. 相似文献
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《测量评论》2013,45(43):284-286
AbstractAs a survey cadet I suppose one accepted the “tricks of the trade” without question. To turn out of the tent at crack of dawn, cook breakfast, and later devote a few idle moments to light pipes, pull on half-dried boots, pack the tucker bag and billy, then set off to work through wet fern and scrub; to boil the billy in the rain-soaked bush, then trek back again at dusk, with more food to cook for supper by the light of a flickering candle,—all added to the day's work, seldom arousing much enthusiasm in the youngest member of the party. Looking back one realizes how much knowledge was gained unintentionally. 相似文献
20.
《测量评论》2013,45(24):68-69
AbstractThe following points occurred to me when reading the interesting paper on crustal equilibrium in E.S.R. No. 23. The principle of compensation or isostasy necessarily involves the idea of two different kinds of rock structure—one strong, the other weak or in extreme cases fluid; for example, there is the familiar case of the strong iceberg resisting change of shape in the liquid sea. In dealing with crustal problems of the earth then, we should make up our minds which part is to be considered as strong, e.g. the granite crust, and which part as weak or fluid, e.g. material at a depth x km. (say roo km.); by weak or fluid I mean that a possibility exists of horizontal movement. 相似文献