In every instance the error of the timepiece used in the observations has been determined with sufficient precision. The observations have been taken on both sides of the meridian, and within ten minutes of the time of culmination, and the reduction to the meridian has been made by the cos L cos D formula a = k (i k = 2 sin2 p m= , cos a -m tan a ¿ cos L cos D, where {i 2 sin1P sin 1" cos a a = 90° + D− L, L = assumed latitude, D= declination of body, pits hour angle, and a correction in seconds. The values of I have been taken from Lee's Tables. In the reductions the second term x = (m tan a {i COS L cos D cos a has not been used. The bodies observed have been so chosen that the altitudes north of the zenith were nearly equal in number and position to those south of the zenith, thus eliminating, as far as practicable, instrumental errors. In all cases where the error of eccentricity was not thus eliminated, the latitude has been corrected for that error as deduced from other observations. Not only have the bodies been carefully selected, and the methods of reduction been the most exact practicable, but each individual altitude was taken with conscientious care. In the whole number of observations made, probably not more than six observed altitudes were rejected in the final computations, and I have no hesitation in presenting the results as worthy of great confidence. Longitudes.-The positions connected in longitude with El Obeiyad by the method of the difference of latitudes and observed azimuths are I do not ask much confidence in the longitudes of the map. The determinations just mentioned have a certain value as checks upon the work with prismatic compass and watch. They are more exact than any independent determinations which I might have made by lunar distances or eclipses, except by a long series of observations; for such a series I had not time. The principal sources of errors in these determinations are1st. They are affected by errors in the longitude of the initial points. 2nd. The azimuths were determined with a magnetic compass too small for great precision; and only at El Obeiyad was the magnetic declination accurately known. 3rd. It was often (usually, in fact) impossible to get the azimuths between precisely the same points at which the latitudes had been found. II. ROUTE FROM EL OBEIYAD TO EL FACHER. The position of El Facher has been determined as follows: For Latitude by Circum-Meridian Altitudes, N. and S. : Licut.-Colonel Mason 10 Observations 1 41 35 Major Prout H. =25 23 45 7 Observations.. 1 41 37.825 24 27 Mean adopted.. .. 1 41 36 4 25 24 06 (East of Greenwich.) As the observations of Colonel Mason were entirely independent of my own as to instruments and methods of reduction, I think that the results are remarkably close and perfectly reliable. On the route from El Obeiyad to El Facher no attempt was made to determine longitude; but the latitude was found at three intermediate points. In the final plotting of the prismatic compass line, the total error was distributed over the whole line; and the errors in latitude between the astronomical stations were distributed over the lines between these stations. NOTE. In constructing the map of Kordofan and Darfur accompanying the above paper, advantage has been taken of other reconnaissances made by officers of the Egyptian General Staff, besides those mentioned by Major Prout. These are generally beyond the area embraced in the map of Kordofan compiled by him, or have been made subsequently. They are as follows: Major Prout: El Obeiyad to El Facher. Colonel Colston: Dabbe to El Obeiyad. Colonel Purdy: Old Dungola to El Facher; upon which the determinations of latitudes and longitudes were made by Lieut.-Colonel Mason. Lieutenant-Colonel Mason: El Facher to Gebal Medob, and return. Captain Mahmoud Sami, under the orders of Colonel Purdy: El Facher to El Touecha, and return. Lieutenant Mahir, under the orders of Major Prout: From El Facher round Gebal Marrah, and return. W. J. TURNER, r.g.s. VI.-Zeno's Frislanda is Iceland and not the Færoes. Admiral IRMINGER. [With Map and Diagram.] By AMONG the voyages of discovery of former times, few have excited more attention among Geographers than the voyages of the Venetian nobles, the brothers Nicolo and Antonio Zeno, to the northern seas, towards the close of the fourteenth century; an account of which was published under the title of Dello Scoprimento dell' Isole Frislanda, Eslanda, Engronelanda, Estotilanda, e Icaria, fatto per due fratelli Zeni, M. Nicolò il Cavaliere, e M. Antonio,' with a map, Carta da Navegar de Nicolo et Antonio Zeni furono in tramontana lano MCCCLXXX.' The latest edition of this work, including the original and an English translation, with notes and introduction, is that by Mr. R. H. Major, published in 1873 by the Hakluyt Society. Many eminent scholars and critics have discussed the Zeno narrative; some arriving at the conclusion that it is untrustworthy or even fictitious, and others that it has much merit. Humboldt says: "On y trouve de la candeur et des descriptions détaillées d'objets, dont rien en l'Europe ne pouvoit leur avoir donné l'idée." * As I have been frequently in those waters, and, besides sailing in the open sea between the islands, have stayed for a long time in Iceland and the Færoe-islands, the old narrative of the Zeni has been from an early date of interest to me, and I have followed the later criticisms of it with constant attention. Some few years since, I took occasion to inform the eminent geographer, Mr. Clements Markham, that my conception of various points in the Zeno voyage did not agree with that of Mr. Major and Admiral Zahrtmann, especially with regard to their identification of the mystic "Frislanda" with the "Færoe-islands." I now take the liberty of submitting to the * Hakluyt edition 1873, Introduction, ix. Royal Geographical Society the grounds on which I differ from the above-named authorities. I will give, first, my critical annotations to Mr. Major's various statements, and then my individual opinion as to the solution of the question in its entirety, constantly referring to the Hakluyt Society's edition of 1873. At page 6 we read the following: "Zichmni then, being such as I have described him, was a warlike valiant man, and especially famous in naval exploits. Having the year before gained a victory over the King of Norway, who was lord of the island, he, being anxious to win renown by deeds of arms, had come with his men to attempt the conquest of Frislanda, which is an island somewhat larger than Ireland. Whereupon, seeing that Messire Nicolò was a man of judgment, and very experienced in matters both naval and military, he gave him permission to go on board his fleet with all his men, and charged the captain to pay him all respect, and in all things to take advantage of his advice and experience. This fleet of Zichmni consisted of thirteen vessels, whereof two only were rowed with oars, the rest were small barques and one ship. With these they sailed to the westwards, and with little trouble gained possession of Ledovo* and Ilofe† and other small islands in a gulf called Sudero, where, in the harbour of the country called Sanestol, they captured some small barques laden with salt fish. Here they found Zichmni, who came by land with his army, conquering all the country as he went. They stayed here but a little while, and making their course still westwards, they came to the other cape of the gulf, and then turning again, they fell in with certain islands and lands which they brought into possession of Zichmni. This sea, through which they sailed, was in a manner full of shoals and rocks; so that had Messire Nicolò and the Venetian mariners not been their pilots, the whole fleet, in the opinion of all that were in it, would have been lost, so inexperienced were Zichmni's men in comparison with ours, who had been, one might say, born, trained up, and grown old in the art of navigation. Now, the fleet having done as described, the captain, by the advice of Messire Nicolò, determined to go ashore at a place called Bondendon,§ to learn what success Zichmni had had in his wars, and there, to their great satisfaction, they heard that he had fought a great battle, and put to flight the army of the enemy; in consequence of which victory, ambassadors were sent from *Little Dimon. † Skuó. Sandó. § Norderdahl. |