6i8 



NATURE 



[Oct. I o, 1878 



■White Swallows 



Mr. Herbert W. Page, in Nature, vol. xviii, p. 540, 

 refers to the rare occurrence of a white Hirundo riparia. 



I may mention that two white swallows of that species were 

 captured in a high bank of sand at Hungryside, on the Forth 

 and Clyde Canal, by Mr. Martin, of that place, in August, 

 1876, which I exhibited at a meeting of the Natural History 

 Society of Glasgow, August 26, 1878. Both birds were white 

 all over, with the exception of a brown tinge on the back of one 

 of them. Mr. Stevenson, in his "Birds of Norfolk," vol. i. 

 p. 342, mentions a light cream-coloured variety got at Eaton in 

 July, 1861, and another at Weasenham in the following Sep- 

 tember. David Robertson, Jun. 



Glasgow, September 27 



Secondary Lunar Rainbow 



During the very stormy and unsettled weather we had about 

 a fortnight ago, I was one of a party of friends on a visit at a 

 country-house near Huntly, about forty miles from this, who 

 were witnesses, on the evening of Sunday, 15th inst., to a very 

 striking, and, as a friend well versed in meteorology has since 

 informed me, very uncommon phenomenon. It was that not 

 only of a complete and brilliant primary lunar rainbow with 

 colours, but also, a few minutes later, of a complete and well- 

 defined, but, of course, less brilliant, secondary bow. No trace 

 of colour could be observed on the secondary, but, inside the 

 primary, the space seemed, in contrast with the faint moonlight, 

 even more brilliantly and uniformly illuminated than I recollect 

 ever to have seen it within a solar rainbow. The time was about 

 eleven o'clock, and the centre of the bows, therefore, bore about 

 W. or a little to the N. of W. R. Walker 



Aberdeen, September 30 



BONE CA VES IN STYRIA » 



I. 'T^WO prehistoric implements, found some years ago 

 ■*■ in the " Badel " Cave, near Peggau, in Styria, 

 are preserved in the Museum of the Johanneum, at 

 Gratz. Count G. Wurmbrand has lately conducted an 

 exploration of this cave. The floor is formed for the 

 most part of a layer of fragmentary stalagmite, about 

 seven centimetres thick, resting on a loam, with bones 

 and gravel, forty-three to seventy centimetres thick. A 

 peculiar laminated and very compact loam, permeated by 

 a blackish substance {pyrohisite) lies on the rocky bottom. 

 In the loam have been found abundant bones and teeth 

 of Ursus spelcEus, undeterminable remains of rodents, a 

 canine of a stag, bones gnawed by hycena, &c., but no 

 human remains or relics. 



2. In a cave on the north slope of the Erzberg, east of 

 Wildalpe, in Upper Styria, Dr. A. Redtenbacher has 

 found abundance of bones and teeth of Ursus spelceus. 

 All these bones, except the phalanges, were broken ; and 

 the long ones of the extremities were split longitudinally. 



3. On July I of this year. Dr. R. Hoernes and Dr. R. 

 von Fleischhaker visited the Drachenhohle (cave of 

 Dragons) near Mixniz, about 1,292 (Austrian) feet above 

 the town, and extending 1,440 feet into the rock, with an 

 entrance 90 feet high and 72 feet wide. The floor of the 

 cave is mostly covered with reddish-yellow cave-loam ; 

 but rock-fragments abound within the entrance. The 

 superficial loam had been searched long ago. The inner 

 parts of the cave, accessible only by ladders, were nearly 

 untouched. On the day mentioned, numerous remains of 

 Ursus spelaus, both young and adult, fragments of jaws 

 with teeth, single teeth, long bones, ribs, phalanges, &c., 

 were soon found. Some of the teeth and bones in the 

 terminal fissure of the cave could have been brought there 

 only by moving water. No other animal but the cave- 

 bear was represented by the remains met with. 



In the portion of the cave next the entrance, a still 

 untouched layer of fragmentary stalagmite, including 

 angular pieces of rock (some very large) was found 



» ImperlaVGeological Institute of Vienna Report, July 31, 1878. 



beneath an accumulation of rock-fragments. Underneath 

 it is an irregular dark-brown and nearly black stratum, 

 about 15 centimetres thick, containing charcoal and 

 partially burnt bones ; and in a brown loam, immediately 

 Jaeneath, similar objects were abundant. These bones, 

 differing from those of the yellowish loam of the inner 

 cave, by their greater consistence and dark colour, belong 

 mostly to Ursus spelcEus, and a few to an undetermined 

 ungulate. The long bones are nearly all broken. Among 

 these dark-coloured bones are phalanges, cervical ver- 

 tebrae, and the lower portion of a right humerus measuring 

 16 centimetres between the condyles, which must have 

 belonged to a colossal individual. The connection of 

 the cei-vical vertebras (the atlas bearing traces of fire), 

 and the presence of several other bones of this individual 

 (as well as those of smaller ones) lead to the conclusion 

 that it was brought into the cave after being killed, and 

 prepared there for the food of the cave-folk. No imple- 

 ments were found. 



OUR ASTRONOMICAL COLUMN 



The Satellites of Mars. — The results of the com- 

 plete reduction and discussion of the Washington obser- 

 vations of the satellites of Mars, undertaken by their 

 discoverer, Prof. Asaph Hall, have just been published 

 by the United States Naval Observatory. The observa- 

 tions of the outer satellite Deimos extend from 1877, 

 August II, to October 31, and those of the inner one^ 

 Phobos, from August 17 to October 15. On November 7 

 and 12 the satellites were looked for, but could not be 

 seen. In treating these observations with the view to 

 the determination of the most probable orbital elements 

 of the satellites. Prof. Hall assumes in the first place 

 that their paths are circular, and by a graphical projec- 

 tion finds the angle between the orbit-plane and the plane 

 perpendicular to the line of sight, as well as the angle of 

 position of the major axis of the ellipse into which the 

 circular path is projected. The resulting elements are 

 then compared with the observations, and elliptical ele- 

 ments deduced from the resulting differences between 

 calculation and observation, both for position and dis- 

 tance, by means of equations of condition. Thus the 

 following values of the elliptical elements have been 

 obtained from the Washington observations alone : — 



Deimos. 



Phobos. 



Epoch 1877, August 28*0 Greenwich Mean Time. 



It will be seen that the planes of the orbits of the satel- 

 lites are nearly coincident with the equator of Mars, the 

 ascending node of which for the above epoch is in 47° 56', 

 and the inclination 39° 45'. Prof. Hall considers the 

 elements to be determined with tolerable accuracy, with 

 the exception of the periodic times, which remain to be 

 decided within closer limits from the observations of 

 another opposition ; nevertheless they are sufficiently 

 exact to carry forward an ephemeris to 1879. The eccen- 

 tricity in the case of Deimos is so small that for most 

 purposes of calculation circular elements will suffice. In 

 the case of Phobos, Prof. Hall thinks the eccentricity has 

 a real existence, every comparison of distance with the 

 circular orbit confirming it. 



The mass of the planet deduced from the measures of 

 Deiinos is 5-357^3, and from those of Phobos ja^lrrej that of 

 the sun being" taken as unity ; the adopted mean value 



