138 



NA TURE 



[December lo, 1891 



In Herr Dr. Wislicenus's experiments, six blinds of varying 

 diameters were employed, and were placed on the cube of the 

 Strassburg meridional circle to represent different central-cone 

 apertures. He measured the difference between the readings taken 

 with and without these blinds on five separate days, in the two 

 positions, horizontal and vertical, of the collimator threads. To 

 still further vary the method, he removed the meridional circle, 

 and placed the blinds on the collimators, making another series of 

 observations, the collimator threads being again in these two 

 positions. From the above measurements he concluded (to state 

 it very briefly) : (i) that the difterences obtained with the Green- 

 wich circle aie of a purely optical nature, and can be easily 

 removed by making the aperture of the central cube somewhat 

 larger than the full aperture of the collimators ; (2) and also if the 

 objective of a telescope be screened quite symmetrically by 

 concentric rings or disks, or by such an arrangement as that in 

 the Greenwich instrument, there occurs not only a variation in the 

 focal image as regards sharpness and brightness, but there can 

 also be found the same displacement. In discussing the 

 observations and conclusions arrived at, he mentions that in the 

 best objectives the same colour rays do not combine in a 

 point on the optical axis, but in such a way that one does not 

 obtain a focus but a focal line of unequal brilliancy, from the 

 brighttst point of which one deduces the focal plane of the lens ; 

 he then goes on to say that since the optical axis of the lens 

 forms therefore an angle with that of the objective, the 

 displacement of the brightest point of the focal line would 

 not fall perpendicular on the focal plane of the lens, but one 

 would have to observe it whh the lens somewhat on one side, 

 by this means one would be able to see its projection on the focal 

 plane of the lens. Therefore, " by the existence of acentering- 

 error the displacement of the focal image by the insertion of 

 blinds before the objective would be explained." 



The Annales of the University Observatory in Vienna, 

 vol. vii., contains all the observations of planets and comets 

 made in the years 1887-89, with the Fraunhofer's, Clark's, and 

 Grubb's refractors of apertures i6"2 cm., 301 cm., and 68'Ocm. 

 respectively, together with the reduced results of the above. 

 In addition to the work mentioned, the Grubh refractor was 

 extensively employed in the study of the nebula in the Pleiades, 

 special attention being given to the Meripe nebula, which forms 

 the chief topic of discussion in the interesting report towards the 

 end of the volume ; an excellent illustration al.-o of the nebula 

 itself is added, in which are shown all the fundamental stars 

 with many others of smaller magnitude. 



Of the other illustrations given, there are three very good 

 pictures of the moon, taken with the same instrument. Plate I. 

 is the result of an exposure of 6 seconds taken on an ortho- 

 chromatic plate, and for sharpness and clearness is excel- 

 lent. Plate II., which is an enlargement of a part of Plate 

 I. enlarged four times is also very fine. Plates IV., V., and 

 VI., contain drawings of comets and nebulie, and are accom- 

 panied with descriptions of their peculiarities. 



Altogether this volume is of a most interesting nature, and 

 shows the result of a great amount of painstaking and useful 

 work, which will be welcomed by all astronomers. 



THE EASTERN TAURUS AND ANTI- 

 TAURUS. 



A T the meeting of the Royal Geographical Society, on Mon- 

 ■^- day evening, the paper read was on the Passes of the 

 Eastern Taurus and Anti-Taurus, by Mr. D. G. Hogarth. 



The paper described the general characteristics, geographical 

 and ethnographical, of the eastern half of the mountain system 

 of Southern Asia Minor, and is based on experience gained by 

 the author in the course of journeys in 1887, 1890, and 1891, 

 undertaken under the auspices of the Asia Minor Exploration 

 Fund, to which the Royal Geographical Society has been a 

 generous contributor. In 1890, Prof. W. M. Ramsay was the 

 nead of the Expedition, and though in the other years the author 

 was not accompanied by him, he followed lines which that great 

 authority on Asia Minor had laid down. Mr. H. A. Brown 

 (author of "A Winter in Albania"), the Rev. A. C. Headlam, 

 of All Souls' College, and Mr. J. A. R. Munro, of Lincoln 

 College, Oxford, took part in the expeditions in different years. 

 The first object of the journeys was archseological, to carry on 

 the brilliant work of Prof. Ramsay commenced in 1881, but the 

 members of the expeditions have always taken geographical 

 NO. I I 54, VOL. 45] 



notes and observations in traversing the interior of Asia Minor, 

 about many parts of which less is known in modern than 

 was known in ancient times. In following old trade-routes 

 across the mountains, he explorers have traced the modern 

 tracks, for the limits of ancient and modern geography are 

 very often not to be distinguished in Asia Minor. Much of the 

 peninsula is a land of the dead, but much also possesses great 

 interest in the present, and, may be, will acquire an interest of 

 a different kind for England in the near future. It has been 

 explored by many travellers, from Pococke, Hamilton, Leake, 

 and Ainsworth, to the archaeologists who have penetrated it in 

 different directions during the past twenty years, and the trained 

 surveyors, led by Sir Charles Wilson, who did so much geo- 

 graphical work in it ten years ago. But Asia Minor is very 

 large, often very difficult to traverse, and of very varied charac- 

 ter, as is to be expected in the meeting-place of so many civiliza- 

 tions and faiths, ancient and modern. Much has yet to be done 

 before western geographers can claim even a superficial know- 

 ledge of its whole area, and many parts have never been visited 

 by any explorer at all. 



The first district described is the wild mountainous region 

 between the beautiful lakes of Egerdir and Beysheher, remark- 

 able for the absence of passes, for the great gorge of Eurymedon, 

 and for the primitive character of the indigenous population who 

 live cut off from the world. Not less noteworthy are the extra- 

 ordinary ruins of the Pisidian city of Adada, which exist high 

 up aniong the hill-tops, and are now called Kara-Bavlo, a name 

 which recalls that of St. Paul, and probably is derived from a 

 great church dedicated to the Apostle in commemoration of a 

 sojourn on his way from Perga to Antioch in 45 A. i). These 

 rums preserve the most perfect specimen of an Anatolian city of 

 Roman days. Passing by the sites of Lystra and Derbe, the 

 Low Taurus is reached, a marked depression between the high 

 inter-lacustrine ranges and the Bulgar Dagh, which begins 

 about 70 miles west of the Cilician Gates (Gulek Boghaz). The 

 waterless, arid character of the northern, and beautiful scenery 

 of the. southern slopes, especially in the Calycadnus valley, are 

 described in connection with the routes radiating from Karaman. 

 The remarkable ruins of the monastery of Koja Kalessi, which 

 contain a very perfect church of the early fifth century at the 

 latest, and of the city of Coropissos, add archjeological interest 

 to this section of the Taurus. The eastern part of this region is 

 a veritable Pompeii, where Roman cities, villages, and roads 

 have been left to decay in a deserted country. 



The high Taurus is reached near Eregli. The famous defile 

 known as the "Cilician Gates" has been often described, 

 but not so the important passes further east, from Sis to Hadjin 

 and Gyuksun ; from Marash to Gyuksun, Zeitun, and Albistan ; 

 and from Adiaman to Besni and Malatia. The Eastern Taurus 

 is a region of great beauty, richly wooded, and traversed 

 by the tremendous canons of the Samanti, the Saros, and the 

 Jihan, not passable even on foot. Whenever a railway is made 

 from Asia Minor towards the Euphrates, it will take the gorge 

 of the latter river, which in ancient times was rendered possible 

 for a road. The ethnographical and historical interest of this 

 region is very great, as it formed the refuge of the last independent 

 Armenians of Cilicia, whose robber-towns, Hadjin and Zeitun, 

 are described by the author. Of late their exclusive possession 

 has been disputed by Circassians and Kurds, the latter retaining 

 curious traces of their pre-Jslamite rites and customs. 



Lastly, the principal passes into the Anti-Taurus from the 

 west, and out on the east in the direction of the Euphrates, are 

 briefly noticed. The Anti-Taurus district is one of the most 

 curious in Asia Minor ; man deserted it almost entirely from the 

 eleventh century until less than a century ago, when nomadic 

 Avshar and Kurds penetrated to its remote and lofty valleys. 

 Thus has been preserved so much of the great Roman military 

 road to the Euphrates in the valleys of the Saros and Gyuk Su, 

 with a series of milestones recording its many restorations ; to 

 the same cause we owe the interesting ruins of Comana, and 

 " Hittite" monuments, recalling very early days, when a great 

 trade-route, afterwards identical with the Royal Persian road, 

 already took this line. Of different but equal interest are the 

 modern inhabitants, nomadic Avshar, and half-troglodyte Kurds, 

 nominally Musulmans, but really worshippers of other gods than 

 that of Islam ; and newly-imported Circassians, settled near 

 troublesome Armenian strongholds as a menace and a check. 

 The medley of races in this remote region, for whose control 

 the Turks seem able to make no adequate provision, suggests 

 speculations as to the possible future of race-supremacy in the 

 Ottoman Empire. 



