268 



NA TURE 



[August 26, 1909 



The Assumed Planet, O, beyond Neptune. — Replying 

 to a critici-sin which appeared in the previous number, 

 Prof. W. II. Pickering has a letter in the current number 

 of the Observatory (No. 412, August, p. 326) in which he 

 recounts some of his reasons for assuming the existence 

 of a planet bej'ond Neptune, whicli is exercising a per- 

 turbati%'e force on Uranus, .\fter pointing out essential 

 differences between the present problem and that which 

 presented itself to Leverrier and Adams, Prof. Pickering 

 states that in the observations of Uranus he finds six 

 distinct deviations from the computed course of the planet 

 which occur where they should if produced by such a per- 

 turbing body as his assumed planet O ; without the 

 assumption three must remain unexplained. He then 

 points out that the Greenwich observations of the 

 last ten years show a steadily increasing deviation 

 from those of the previous sixty years, a deviation 

 which he considers is, of itself, a strong argument in 

 favour of the existence of a hitherto unrecognised disturb- 

 ing force. 



With regard to the suggestion, made in Nature for 

 June 17, that the time is ripe for the discussion of the 

 observations of Neptune, for the determination of any 

 perturbing influence, Prof. Pickering suggests that such a 

 discussion would probably be more hopeful in twenty years' 

 time, when the deviations of Neptune should amount to 

 two or three seconds. Another maximum of Uranus will 

 occur about then, and a graphical solution would be likely 

 to furnish trustworthy data concerning the perturbing 

 force, or forces, very quickly. 



AGRICULTURE IX THE TRANSVAAL. 

 'pHE issue of the annual report of the Transvaal De- 

 partment of Agriculture is an important event in 

 the agricultural world, and each year's report furnishes 

 fresh proof of what science can do for agriculture. The 

 work has outgrown the accommodation, and Mr. Smith 

 puts in a strong plea for buildings which, in the Trans- 

 vaal, is not likely to be disregarded. 



An account is given by the heads of the separate depart- 

 ments of the work that has been going on. Dr. Theiler 

 reports further experiments with Piroplasma mtitans and 

 P. bigentiiium, two organisms causing serious animal 

 diseases, and is making considerable progress with in- 

 oculation methods of coping with them. The botanical 

 division, under Mr. Burtt-Davy, has occupied itself with 

 the improvement of the seed maize. Already the Transvaal 

 farmer exports maize, and could export more ; he would 

 secure higher prices and greater profits if supplies of trust- 

 worthy seed were available. New and promising plants 

 have also been investigated, and one or two appear as if 

 they will be useful, especially the Florida beggar weed, a 

 leguminous plant suitable for the bushveld, and much liked 

 by stock. 



The plant pathologist, Mr. Pole Evans, finds that the 

 potato-rot fungus, Nectria solani, Pers., hitherto regarded 

 as a saprophyte, is, in the Transvaal at anv rate, an active 

 parasite, attacking the tubers at all stages of growth, and 

 causing a putrid rot in them while still in the soil. Infected 

 potatoes are not admitted into the Transvaal, and steps 

 are being taken to eradicate the disease, but the other 

 South African colonies are doing nothing to prevent the 

 disease from establishing itself within their borders. A 

 uniform system of dealing with plant diseases will be not 

 the least among the advantages of unification. 



Locust destruction has received much attention from the 

 Entomological Division. There was a serious invasion of 

 brown locusts, doing damage estimated at about 1,000,000!., 

 but the swarms were marked down, and the voetgangers 

 destroyed by spraying with sodium arsenite solution. Un- 

 fortunately, some of the farmers and manv of the natives 

 are still indifferent about the work, and look upon locusts 

 as a scourge against which it would be impious to con- 

 tend ; thus places where eggs are laid are not always 

 notified. 



There is also a general rise in the standard of agriculture 



in the colonies, in which the experimental farrns of the 



department have played a conspicuous part. An increased 



area of land has come under the plough. Thrashing 



NO. 2078, VOL. 81] 



machines are being used more commonly ; wheat is being 

 taken up. The quality of the live stock is improving ; 

 there is a large demand for well-bred animals, and com- 

 petition for the pedigree stock raised on the Government 

 farms is very keen. Some farmers are interesting them- 

 selves in ostrich farming, which is likely to be a valuable 

 industry in some parts of the colony, where the wild birds 

 are fairly numerous. 



Altogether the record is a highly satisfactory one, and the 

 director, Mr. F. B. Smith, and the staff, are to be con- 

 gratulated on what they have accomplished. 



SPONTANEOUS COMBUSTION. 

 ]~)R. JOHN KNOTT has published in the New York 



Medical Journal (April 17 and 24) an article on 

 spontaneous combustion, with the object of showing that 

 the cases of death reported as occurring from that cause 

 are mere fancy legends which were partly the result of 

 ignorance and mainly of imagination. Many years ago 

 Liebig, and later Casper, wrote treatises with the same 

 object ; but Dr. Knott's contribution is not devoid of 

 interest, if only for the exhibition of gentle sarcasm with 

 which he attacks the writings and statements of past 

 Fellows of the Royal Society and others of equal stand- 

 ing who lent the sanction of their names to these idle 

 fables. He does not include among his cases the one 

 which is probably best known to English readers, namely, 

 the celebrated case of Mr. Krook recorded by Dickens in 

 " Bleak House." The evidence in favour of spontaneous 

 combustion as the cause of Mr. Krook's death is just 

 about as convincing (or the reverse) as in the majority 

 of the others. 



We fancy, however, that Dr. Knott is preaching to the 

 converted, for we can hardly believe him when he states 

 that " spontaneous combustion is still accepted as an 

 article of pathological faith by our recognised leaders in 

 the domain of medico-legal opinion and teaching." 



The belief In spontaneous combustion in the human body 

 doubtless originated in the observation of electrical pheno- 

 mena long before electricity was understood or even dis- 

 covered. The " will-of-the-wisp " was endowed, as its 

 name suggests, with a personality. The saintly halo and 

 the fiery tongues of painters and poets familiarised the 

 onlooker with imaginary exhalations ; the easy combusti- 

 bility of certain organic substances, the occurrence of 

 phosphorescence in the sea and in decaying organisms, 

 were then mysteries which combined to lend credence in 

 an unusual combustibility of the human frame in those 

 inclined to believe in the miraculous on the slenderest of 

 evidence. 



This point of view was accentuated and stimulated by 

 the discovery of a new element, phosphorus, especially as 

 it was first isolated from human urine and bones. The 

 discovery of phosphorus in its day excited just the same 

 kind of interest and imaginative thought as the discovery 

 of radium is doing at the present time. 



ETHNOLOGY IN AMERICA. 



'T'HE American Ethnological Society has reprinted in 

 facsimile the first part of their Proceedings, originally 

 published in 1853. The most interesting article is that 

 contributed by W. Bartram, which was written in 1789, 

 entitled " Observations on the Creek and Cherokee 

 Indians," being replies to a series of ethnological ques- 

 tions prepared by Dr. B. S. Barton, vice-president of the 

 Philosophical Society of Philadelphia. The connection of 

 this tribe with the Iroquois, of whom they formed the 

 southern branch, has now been established by Horatio 

 Hale and Gatschet. This paper gives a singularly interest- 

 ing account of the ethnography of a tribe now practically 

 extinct, describing their probable origin, relations with 

 other tribes, their picture records, religious beliefs, forms 

 of tribal government, physical characteristics, social rela- 

 tions, their " Chunkey-yards " or earthworks, tenures of 

 land and conditions of property, diseases and their 

 remedies, food and means of subsistence. In connection 

 with the divine kings of Prof. J. G. Frazer, it is interest- 



