Terrestrial and Celestial Globes Volume 2 / Their History and Construction Including a Consideration of their Value as Aids in the Study of Geography and Astronomy

by Edward Luther Stevenson

Fig. 122. Terrestrial Globe of John Senex, 1793.

The British Museum likewise possesses one of Senex’s terrestrial globes, which seems to be practically like that to be found in the Madrid Library.

It will have been noted that many of those reputed to have been globe makers in these early years did not actually apply themselves to the constructive mechanical work, this being passed over to skilled artisans, to workers in metal and wood, to engravers and to mathematical instrument makers, who, if possessing generally recognized ability, often insisted on having their names associated in the author legends with the real authors of the globes. Nicolas Bion (1652-1733) may be cited as an excellent example of such a skilful workman, achieving in his day great distinction as a globe maker.[137] He seems not to have thought of himself as one meriting special honors as geographer, cartographer or astronomer (Fig. [123]). By reason of his marked abilities, exhibited in the manufacture of mathematical instruments, he was honored by his royal patron with the title Engineer of the King for Mathematical Instruments. Through his principal work,[138] a treatise on the construction and uses of globes in which the subject is treated in both a theoretical and a practical manner, he is entitled to rank with the leaders of the century in this particular field of scientific endeavor. True to the spirit of the age Bion gave much thought to the idea of reform in the matter of globe construction, especially in the matter of fashioning globe gores and their attachment to the surface of the sphere. He seems to have prospered in his business, and we are told by his son that he constructed numerous armillary spheres, likewise many terrestrial and celestial globes of various sizes. Reference is made above to a task assigned to him by the great astronomer, Cassini.[139]

A few of the globes of this distinguished man have been located. Fiorini reports[140] that one of his celestial globes may be found in the private library of Count Malvezzi de’ Medici of Bologna, having a diameter of about 32 cm. Its twelve gores have been cut at latitude 70 degrees both north and south, the polar spaces being covered by four sectors instead of by the usual circular disc. The globe is made to revolve on its equatorial axis, not on the axis of the ecliptic. It has a simple mounting, including a meridian circle of brass and a horizon circle of wood. Star names are given in French and in Latin. The dedication reads, “Dédié et présenté à Monseigneur le Dauphin par son très humble et très obéissant Bion,” but there appears to be some uncertainty about the date, which is probably between 1700 and 1710. There is one of Bion’s terrestrial globes dated 1712 and dedicated to “Monseigneur le Duc de Berry,” in the Istituto tecnico of Florence, which is reported to be in a good state of preservation. Loxodromic lines are drawn on the map in accord with the best practices of the time, which radiate from wind or compass roses, one being placed on the equator and one at latitude 35 degrees south. A third terrestrial globe made by Bion may be found in the Osservatorio Astronomico of Rome, which is wanting both dedication and place of publication.

The Osservatorio Astronomico also possesses a fine armillary sphere, the work of Carmelo Cartilia,[141] the diameter of whose largest or meridian circle is about 26 cm. It is described by a former director of the observatory as being made of brass, and a companion of a globe constructed by Bion, having a similar mounting. The equatorial circle, the tropics, and the colures have the usual graduation. The ecliptic consists of a band 4 cm. in width, having engraved on its surface the signs of the zodiac and the days of the months. At the north pole is attached an hour circle with index. At the common center of the circles is a small ball 27 mm. in diameter representing the earth, through which the axis of the ecliptic passes. Around this small ball is adjusted a circle on which is engraved the word “Luna.” There is an additional small circle which represents the course of the sun, and attached to this is a silvered ball to represent that luminary. Circles are provided representing the planets, on which we find such names as “Marti,” “Giove,” “Saturno,” and circles around the sun representing the course of the planets Mercury and Venus. On one of the supporting arms of the sphere is the author and date legend, reading, “Carmelus Cartilia et Francalancia Siculus fecit Taurini anno dñi 1720.”

Mattheus Seutter (1678-1756) was a map and globe maker of this period, whose activities centered in the city of Augsburg.[142] His early training as engraver was received in the establishment of Johann Baptista Homann in the city of Nürnberg, but in the year 1707 he established himself in his native city, Augsburg, setting up an independent business for the production of maps, globes, and mathematical instruments. Seutter holds his place in the history of cartography not so much by reason of the high quality of the work done as by reason of the quantity.[143] The number of maps, large and small, battle plans and city plans, charts geneological, chronological, and heraldic, which he published may be counted by the hundreds, the majority being modified copies of maps and charts which others had previously issued. As a reward for the dedication of his large atlas to the Emperor Charles VI, issued in the year 1725, he was named “Imperial Geographer,” a title which had been held by Homann until his death in the year 1727.

Following the practice of the more prominent map makers of the period, Seutter turned his attention to globe construction, and not a few examples of his work can still be found. Some of his globes were of large size, having a diameter of about 160 cm. The terrestrial as well as the celestial globe balls he covered with twelve engraved sections, or twice twelve, these being cut at the line of the equator, and at latitude sixty-seven both north and south, the polar space being covered, as was usual, with a circular cap or disc. The mountings of these globes consist of a wooden meridian circle and a graduated wooden horizon circle, having each on the upper surface the usual concentric rings with the names of the months, the names and signs of the zodiacal constellations, and the names of the principal winds, the whole being supported by two semicircles attached below to a single columnar base 28 cm. in length. A brief author legend reads, “Globus terrestris juxta recentissimas observation: et navigation: peritissimor: Geograph: delineat. cura et sumptibus Matth. Seutteri Calcogr: August.” “Terrestrial globe according to the most recent observations and voyages of the most skilled geographers. Made by the labor and at the expense of Mattheus Seutter renowned engraver.”

The maps on these globes present no features of special scientific value, the author following in the main the best contemporary geographical and astronomical records. It should, however, be noted that he introduced an improvement in the construction and printing of the circular polar discs. To the end of remedying the difficulty in attaching this part of the covering, having observed, as others, that the paper would expand with the application of paste, and could therefore not be adjusted with the strictest accuracy and nicety, he conceived the idea of cutting from this disc a very small section or small sections, so that when it was applied to the sphere after being moistened with the paste the amount of stretching was sufficient to cover the space. In other words, he made his circular disc one of 350 degrees instead of one having the full 360 degrees. In this connection, it might be noted that the quality of the paper was an element always to be taken into account in calculating the amount of expansion after moistening.

A pair of Seutter’s globes may be found in the Biblioteca Comunale of Macerata. A copy of the terrestrial is reported in 1892 to have been in the private library of Professor Maximilian Tono of Venice, a pair in the Museo Astronomico of Rome (Figs. [124], [125]) and also in this museum may be found a complete set of the gores for one of his terrestrial as well as a set for one of his celestial globes, but which by Professor Jacoli of Venice have been thought to be reprints and not originals. A copy of the celestial globe may be found in the Biblioteca Universitario of Urbino.