Globe (map)

“ The globe itself rotates within a metallic meridian to which its axis is attached. Other accessories are an hour-circle, around the north pole, a compass placed beneath the globe, and a flexible quadrant used for finding the distances between places. These accessories are indispensable if it be proposed to solve the problems usually propounded in books on the “use of the globes,” but can be dispensed with if the globe is to serve only as a map of the world. The size of a globe is usually given in terms of its diameter. To find its scale divide the mean diameter of the earth (1,273,500 m.) ”

“ It has a supporting base of four artistically turned columns with binding crossbars extending from each post to a central circular plate 17 cm. in diameter, carrying the post through a slot in which the meridian circle is made to pass. The north pole is topped with a thin pasteboard hour circle and pointer. The globe map is composed of twelve gores which are truncated in latitude 80 degrees both north and south, the polar spaces being covered with circular discs, and are cut on the line of the equator. The sphere is exceedingly light in weight, being composed of papier-mâché. ”

“ Numerous barbaric kings are represented in picture, likewise numerous animals of land and sea, and ships artistically drawn sail hither and thither over the oceans. The austral continent is wanting. Marcel especially notes the striking resemblance of the globe map to the Mercator map of 1569, suggesting the possibility of its Mercatorian origin, in support of which suggestion he quotes a number of geographical names as well as certain legends. The globe, it appears, has never been critically studied, but is clearly an interesting geographical monument of the period. ”

“ O powerful Caesar! we have, here also in this map of land and sea, made use of a new division of the globe; namely, at the equator, so that each half of the globe thus divided has one of the poles as its center. By depressing the pole to the plane of the equator and by making incisions from the equator to the pole, we have made a projection similar to that presented to the public on the other map with detached poles and with the meridians separated on the same plane, without disregarding the correct dimensions of the longitude, latitudes, degrees, parallels, and climates. ”

“ It was this great Alexandrian cosmographer who first demonstrated the scientific value of drawing on the surface of a globe or map the network of parallels and meridians, and of establishing by means of the two geographical coördinates the true geographical position of every known place. To the end of making globes more serviceable he suggested the use of a meridian circle, such as is today employed in globe construction, passing through both poles, within which circle the globe might be made to move freely on its axis. ”

“ If the earth is a sphere then why could a map so draughted as truly to represent the surface of a sphere not be counted the most acceptable? This must have been the argument of those who especially applied themselves to the designing of maps suitable for a spherical surface, that is, for application to a globe ball. ”

“ The poor calligraphy suggests that it is not the work of an expert cartographer, but of one who somewhat hastily and carelessly had undertaken to copy a globe map of the type represented in the work of Franciscus, of the maker of the Paris Gilt globe, or of Schöner in his 112globe of 1533. Meridians are represented at intervals of ten degrees commencing at a prime meridian which passes through the Cape Verde Islands, while the parallels are similarly marked, the graduation being indicated on the prime meridian. ”

“ The terrestrial globe, in a much better state of preservation, contains, in a neat cartouch, an address to the reader, explaining the merits of the globe map: “Quandoquidem quotidiana diversarum nationum, praecipue tamen Holandorum navigatione omnes mundi plagas perlustrantium, varii orbis tractus, remotae insulae et quamplurima regna hactenenus incognita nunc in dies innotuere, et quae fuere cognita majori studio et situs observatione perlustrata sunt. Prodit hic noster Globus multo praecedentibus a nobis editis, qui primi in his provinciis prodierunt accuratior et emendatior. ”

“ A globe can be accurate, in the sense that everything is produced to scale, but a flat map cannot be. I am not talking of practical difficulties, I am talking of a theoretical impossibility. For example: the northern halves of the meridian of Greenwich and the ninetieth meridian of west longitude, together with the piece of the equator between them, make a triangle whose sides are all equal and whose angles are all right angles. On a flat surface, a triangle of that sort would be impossible. On the other hand, it is possible to make a square on a flat surface, but on a sphere it is impossible. ”

“ The sphere is then coated with plaster or whiting, and when it has been smoothed on a lathe and dried, the lines representing meridians and parallels are drawn upon it. Finally the globe is covered with the paper gores upon which the map is drawn. The adaption of these gores to the curvature of the sphere calls for great care. Generally from 12 to 24 gores and two small segments for the polar regions printed on vellum paper are used for each globe. ”

“ Terrestrial Globe of Jodocus Hondius, 1618.
The map is slightly water-stained, but the American portion is particularly well preserved. A crack in the sphere along the meridian of 150 degrees east extends from pole to pole, and is rather a disfigurement than a serious injury to any part of the surface. The map is a remarkably fine example of the Dutch map engraver’s art. ”

“ Which, if my reader can at present do—or at least refer to a fairly drawn double-circle map of the globe with converging meridians—I will pray him next to observe, that, although the old division of the world into four quarters is now nearly effaced by emigration and Atlantic cable, yet the great historic question about the globe is not how it is divided, here and there, by ins and outs of land or sea ”

“ The terrestrial globe is covered with a manuscript map in colors, and bears the title legend “Nova ac generalis orbis descriptio,” and the author legend “Caspar Vopel mathe. faciebat.” Most of the regional names on the map are in red, and a red dot is employed to indicate the location of certain important cities, the names in general being omitted. The globe is remarkably well preserved (Fig. 56) . ”

“ This difficulty the globe makers, of course, were continually seeking to overcome or reduce to a minimum, as the years passed, through a careful selection of205 paper to be used, through a more skilful manipulation of the paper made moist by the application of the paste or glue employed in attaching the map to the surface of the sphere,197 and through a more careful working out of the mathematical problem having to do with the proper proportions of each of the gores. ”

“ General problems to be met.—Development from the simple armilla to the complex sphere.—The references of Ptolemy, Leontius Mechanicus, Alfonso.—Behaim’s leadership in practical globe making.—Materials employed.—Experiments in map projection.—The beginning and rapid development of globe-gore construction.—Various examples of early gore maps.—Equatorial polar and ecliptic polar mountings.—Special features of celestial globe maps.—Globe mountings.—Varying sizes of globes.—The uses of globes.—Moon globes and planetariums. ”

“ My 'Handbook of the Stars' has been prepared to aid the student in the construction of such maps.
In selecting maps it is well to be able to recognise the amount of distortion and scale-variation. This may be done by examining the spaces included between successive parallels and meridians, near the edges and angles of the maps, and comparing these either with those in the centre of the map, or with the known figures and dimensions of the corresponding spaces on a globe. ”

“ Even a general map may be trusted, as long as we keep within ten degrees of its centre. In the case of more considerable distances, however, a globe of suitable size should be consulted, or—and this seems preferable—they should be calculated by the rules of spherical trigonometry. The problem then resolves itself in the solution of a spherical triangle.
In the formulae which follow we suppose l and l′ to represent the latitudes, a and b the co-latitudes (90 − l or 90° − l′) , and t the difference in longitude between them or the meridian distance, whilst D is the distance required. ”

“ Its twelve segments are fashioned to terminate at the poles of the ecliptic, instead of at the poles of the equator, a practice not uncommon. The globe has a simple mounting of wood, is reported to be in good condition, and may be found in the Liceo Marco Foscarini of Venice, to which library it came, in the year 1807, from the Convent of S. Georgio Maggiore.
It is not a little surprising that our information is so meager concerning men as active in the field of map and globe making as were Gerhard and Leonhard Valk in the latter part of the seventeenth and early eighteenth century. ”

“ Some kinds of apparatus have long been found in schools. Geography has long had the aid of maps, and no teacher would use a geography which was not furnished with a respectable atlas. But maps alone are not a sufficient apparatus in teaching geography. A globular revolving map of the world, a globe, and a cylindrical revolving Mercator's chart, will furnish important aid in explaining the globular, polar, and Mercator's projections of a map of the world. Astronomy and natural philosophy can no more be successfully taught without the use of machines, than can geography without the use of maps. ”

“ The twelve gores of the map have been mounted so as to join at the north and south poles of the ecliptic, there however being a small covering disc at each pole, so frequently employed since Mercator’s day, the globe itself being made to revolve on its equatorial axes. ”

“ Granting that some Princes and certain others do have maps very large, as for example, such as Pope Paul II had made for the palace of S. Marco in Rome, there are also Princes and private persons who have globes which in size much surpass the plane maps that I 155have ever seen or heard of.” “Until a few years since no one knew how to print such globes, and all were made with pen and brush, ... later geniuses have found a way for printing globe maps very accurately, which, in a wonderful way they can place over the surface of a sphere ”

“ As the years passed, and the engraved map found increasing favor, practically all globe balls, with exceptions as noted above, were made either of plaster shot through and through with a binding material, usually of fiber, and fashioned over a mould, or of a preparation of papier-mâché.
The increasing interest in globes and globe making manifesting itself in the early years of the sixteenth century led to the devising of methods for their more rapid construction. ”

“ James, Thomas, explorer, II, 17 Jomard, E. F., obtains an Arabic globe in Egypt, I, 31 Julius I (Pope) , globe belonging to, I, 62 Kahira, Public Library, I, 28 (Ptolemy) Kepler, Johann, reference to Apianus globe, I, 177 Ko-Shun-King, Chinese astronomer and globe maker, II, 129 Kúblai Kaan, interested in globe making, II, 128 Lactantius, allusion to Archimedes’ globe, I, 17 Laon, City Library, I, 51 (Laon globe) Latitude and longitude, methods of determining, II, 141, 142, 171, n. 128 Lattré, map engraver, II, 182 Leiden, University Library, II, 27 (Blaeu) ; 66 (Janssonius) . ”

“ As the mariners’ compass points north and south at one and the same time, and a meridian is a north and south line, it follows that meridians can be no other than straight lines. But, since all meridians on a globe are semicircles, it is an incontrovertible proof that the Earth is not a globe. ”

“ A terrestrial globe without any mechanism, so long as its axis is parallel to that of the earth, exposed to the direct rays of the sun, represents our planet with its recurrence of day and night.
The figure (634) shows us a globe without any support. The axis is north and south, and makes, with the horizon, an angle equal to the latitude of Paris, if the support, A B, be horizontal. To make the axis of the globe parallel to the axis of our earth, the line, N S, must correspond to the meridian of the place ”

“ It is not supplied with a movable meridian circle, but within the horizon circle, from north to south, and from east to west, there are two brass half circles, of the same diameter as the horizon circle and so adjusted as to form one piece with it. Through such an arrangement it is made possible to turn the globe in any desired direction, one half of it being at all times above the horizon. ”

“ Referring again to the diagram, Figure 19, the vessel may sail from the north towards the south, upon the meridian Figure 1, and there turning due west, may pass Cape Horn, represented by D, and continue its westerly course until it passes the point C, or the Cape of Good Hope, and again reaches the meridian, Figure 1, upon which it may return to the north. Those, then, who hold that the earth is a globe because it can be circumnavigated, have an argument which is logically incomplete and fallacious. ”

“ It has been shown that meridians are, necessarily, straight lines; and that it is impossible to travel round the Earth in a north or south direction: from which it follows that, in the general acceptation of the word “degree,”—the 360th part of a circle—meridians have no degrees: for no one knows anything of a meridian circle or semicircle, to be thus divided. But astronomers speak of degrees of latitude in the same sense as those of longitude. ”