April 29, 1880] 



NATURE 



627 



seven horns, three in pairs, and one single ; they are denned 

 as the "supraparietal," " supratemporal," and " post-orbital " 

 pairs ; the single and symmetrical horn is "nasal." 



In the comparison of this character with the known genera of 

 lizards the author finds the closest correspondence in the dimi- 

 nutive existing Australian species, Moloch horridus, Gray. He 

 concludes with remarks on the probable habits and conditions of 

 extinction of the subject of his two papers. 



"Report on the Exploration of the Caves of Borneo," by A. 

 Hart Everett. "Introductory Remarks," by John Evans, 

 DC.L., LL.D., Treas. R.S. And "Note on the Bones 

 Collected," by G. Busk, V.P.R.S. 



The general result of the exploration may be summed up as 

 follows : — The existence of ossiferous caves in Borneo has been 

 proved, and at the same time the existence of man in the island 

 with the fauna, whose remains are entombed in these caves. 

 But, both from the recent nature of this fauna, and from the fact 

 that the race of men whose remains are associated with it had 

 already reached an advanced stage of civilisation, the discovery 

 has in no way aided the solution of those problems for the 

 unravelling of which it was originally promoted. No light has 

 been thrown on the origin of the human race— the history of the 

 development of the fauna characterising the Indo-Malayan sub- 

 region has not been advanced — nor, virtually, has any evidence 

 been obtained towards showing what races of men inhabited 

 Borneo previously to the immigration of the various tribes of 

 Malayan stock which now people the island. Furthermore, the 

 presumption that the north-west portion of Borneo has too 

 recently emerged above the waters of the sea to render it 

 probable that future discoveries will be made of cave deposits 

 of greatly higher antiquity than those already examined, has 

 been strengthened. Under these circumstances it seems ad- 

 visable that cavern-research in north-west Borneo should now 

 be left to private enterprise, and that no further expense should 

 be hazarded, at any rate until the higher parts of the island in 

 the north-east may be conveniently examined. 



"Note on the Collection of Bones from Caves in Borneo, 

 referred to in Mr. Everett's Report on the ' Exploration of the 

 Bornean Caves in 1878-9,'" by George Busk, F. R.S., V.P. 

 Anth. Inst 



These bones present nothing of especial interest ; and with 

 respect to the race to which they may have belonged, the infor- 

 mation they have afforded is very meagre. On this point all 

 that can be said is that they may well have belonged to the 

 Malay type, but there is also no apparent reason why they 

 should not have been of Chinese origin. VVhat tends to afford 

 some support to this supposition is the marked fulness or bulging 

 of the squamosal in the sphenoidal fossa, to which I have called 

 attention, and which, upon examination of the collection o f 

 crania in the Royal College of Surge. >ns, I find is presented by 

 several among the Chinese crania in a more marked degree than 

 in the other races to which my attention was directed. 



Physical Society, April 10. — Prof. Fuller in the chair. — 

 New members:— Mr. \V. O. Smith, Prof. Judd, F.R.S.— A 

 paper on the human eye as an automatic photometer, by Mr. 

 William Ackroyd, was read. It is difficult to get the value of a 

 very intense light in terms of a weak one, because the relative 

 physiological values of the sinvlarly coloured constituents are 

 unknown. The author's experiments were made to show that 

 the eye itself is a fairly good light measurer. When a "spot" 

 or star of light is looked at from a distance, it is seen to emit 

 ' ' rays " or spokes of light at all angles. These are due to the 

 radiate structure of the crystalline lcn~ and to the lachrymal fluid 

 on the surface of the corner of the eye. The rays are of vari us 

 lengths and are shorter in the 1st and 2nd quadrants, next the 

 nose, near the blind spots, than on the 3rd and 4th quadrants — a 

 fact probably due to the insensibility of this region. The iris 

 expands and contracts under the stimulus of light independently 

 of the will; and both irises act sympathetically. Now the iris 

 lies between the seats of irregular refraction, and thus any change 

 in the size of the pupillary aperture will be rendered evident by 

 an alteration in the length of the longer rays of a spot or point 

 of light. On this fact is based the u-e of the eye as an automatic 

 photometer. The sensitiveness of the iris varies in different 

 persons. The author finds that a sperm candle, burning 120 

 grains per hour, produces a distinct movement of his iris w hen 

 14 yards distant. In employing the eye as a photometer, the 

 author adopts the principle that if the light from one source A 

 falling on the eye is capable of producing movement of the iris 

 at a distance d, and the light from a different source B is capable 



of producing the same movement at the distance <i", then the 

 relative intensity is proportional to the squares of these dis- 

 tances. To carry this out in practice the observer is in the 

 dark, and an artificial star is placed on a level with the eyes 

 at a fixed distance. Below this is placed the light to be tested in 

 the same plane. While gazing steadily at the star the other 

 light is to be eclipsed and revealed, and the observer is to find a, 

 position where the revealing of the second light does not influence 

 his iris, as shown by no apparent shortening of the rays of the 

 star taking place. He then approaches gradually till a second 

 position is reached, when the revealing of the second light 

 does produce a movement of the iris. The distance between 

 his eye and the light, d, is measured. A third light is 

 now put in place of the second, and the same observations re- 

 peated, so as to get a second distance, d'. From these distances 

 the relative intensities are calculated ; the author's results agree 

 pretty closely with Rumford's photometer, but he found that for 

 some reason the two first observations have to be discarded as 

 too inaccurate. Owing to the sympathy between the two irises 

 these experiments were binocular. This sympathy may prove 

 convenient in constructing an eye-photometer, .since one eye 

 can be turned to the light to be estimated while the other is 

 looking at the artificial star. This method of photometry would 

 be too delicate for comparing powerful electric lights, unless 

 aided by mechanical means. — Prof. Ayrton then offered an 

 explanation of the experiment shown by Prof. Guthrie at last 

 meeting to the effect that while flannel rubbed with ebonite was 

 + electrified, and ebonite rub! ed with, glass was + , flannel 

 rubbed with glass was - . Prof. Ayrton accoanted for this 

 apparent anomaly on the ground that one or more of the 

 substances was an electrolyte. Glass, for instance, is an electro- 

 lyte, and a battery had been made from it. Experiments made 

 by Prof. Perry and himself had shown that in a " pile " made up 

 of divers substances, one or more of which were electrolytes, 

 though the rest were metals, the electromotive force of the pile 

 was equivalent to the algebraical sum of the several "pairs" 

 composing it, but it was not equivalent to the electromotive 

 force of the first and final plates made into a pair. That could 

 not be predicated from the contact-electromotive forces of the 

 elementary "pairs." When only metals were employed it could, 

 but not in cases where an electrolyte entered. This same result 

 would apply to Prof. Guthrie's frictional experiments. In 

 answer to Prof. Guthrie's question w hether electrolysis did not 

 come into play in Prof. Ayrton's experiments, Prof. Ayrton 

 replied that it could not operate to a greater extent than in Prof. 

 Guthrie's experiments, as he had used a quadrant electrometer. — 

 Dr. Stone then described a new tonometer devised by Prof. 

 Rudolf Kbnig, which he had recently seen in Paris. It con- 

 sisted of a clock-work working into a tuning-fork, which pro- 

 duced no less than 128 escapes per second. To this clock-work, 

 originally invented by an assistant of M. Breguet, and exhibited at 

 the Paris Exhibition of 1856, Prof. Konig had added a Helm- 

 holtz vibration microscope moved by the clock and the fork, 

 whose vibration number to be measured is placed vertically in 

 the focus of the microscope. The tonometer is very portable, 

 and no loading of the fork is required. Prof. Hughes observed 

 that he had patented a vibrating regulator in 1856. — Dr. Guthrie 

 then exhibited an electric machine formed of a collodion disk 

 rubbed with a cat's fur, and giving negative sparks. The collo- 

 dion, after a suggestion of Capt. Abney, was put on by giving a 

 disk a coat of collodion, then a coat of india-rubber dissolved in 

 benzol, then a coat of collodion again. Prof. Guthrie also 

 showed that an iron cylinder revolving round its longer axis, and 

 with a current flowing in a wire parallel to it, has power to 

 deflect a magnetic needle. Prof. Ayrton stated that he had 

 found the mere rotation of an iron cylinder produced the deflec- 

 tion in question, and therefore thought the current was not 

 required to produce the effect shown. 



Philadelphia 



Academy of Natural Sciences, November 11, 1879. — Cm 

 a collection of Crustacea from Virginia, North Carolina, and 

 Florida, with a revision of the genera of Cragonidas and Pala> 

 monid;e, by J. S. Kingsley. 



November iS. — On the stratigraphical evidence afforded by 

 the Tertiary fossils of the Peninsula of Maryland, by Angelo 

 Heilprin. 



December 9. — Description of a fcetal walrus, by Dr. Harrison 

 Allen.— Complete connection of the Fissura centralis (fissure of 

 Rolando) with Forsa sylvii, by Dr. A. J. Parker. 



