482 



NA TURE 



[September 15, 1892 



Here is the Hall apparatus on a small scale. It is simply a 

 carbon-lined iron crucible, and a thick stick of carbon. As 

 already mentioned, the crucible is the cathode, the stick of 

 carbon the anode. 



As the process takes time to get into full operation, it was 

 commenced some hours ago, and at the rate at which it has 

 been working we should by now have produced several ounces 

 of aluminium. In beginning the process the charge has first to 

 be melted. This is done by bringing the carbon stick into con- 

 tact with the bottom of the crucible, so as to allow the current 

 to pass from carbon to carbon to develop heat between the 

 electrodes. 



The alumina compound, which, when melted, forms the bath, 

 is added, in powder, litile by little, and, when sufficient is 

 melted, the carbon stick is raised out of contact with the bottom, 

 and the electrolytic action then commences. 



I will now ask Mr. Sample to empty the crucible and let us 

 see the result of the operation, and while he is doing so I take 

 the opportunity of expressing my very sincere thanks for his 

 having so kindly and so successfully carried out this most inter- 

 esting demonstration of the latest and one of the most 

 important of all the applications of electricity to metallurgical 

 operations. 



Here is the result of our experiment. It is not very large 

 certainly, but it is quite enough for our purpose, which is to 

 illustrate the principle of a newly developed electro-metallurgical 

 industry directly derived from discoveries made at the Royal 

 Institution. 



MOUNT MILANJI IN NYASSALAND. 

 1-1 ID DEN in the recesses of one of the recently issued Par- 

 ■*■■'■ liamentary Papers (Africa, No. 5, 1892) will be found a 

 very interesting report on the mountain and district of Milanji, 

 in British Central Africa, by Mr. Alexander Whyte, F.Z. S., one 

 of Mr. Commissioner Johnston's principal assistants in the task 

 of ruling and developing the new British Protectorate of Nyassa- 

 land. Mr. Whyte was sent to Milanji by Mr. Johnston in 

 October last, and dates his report from the " Residency, Zomba, 

 British Central Africa," in the month following. Milanji is a 

 large mountain mass in the extreme south-east corner of Nyassa- 

 land, drained on the west by the head waters of the Ruo, one of 

 the affluents of the Shire, and on the east by the Lukuga and 

 other smaller streams, which run into the Indian Ocean north 

 of the Zambesi. It is described by Mr. Whyte as an isolated 

 range of, for the most part, precipitous mountains, the main 

 mass forming a huge natural fortress of weather-worn preci- 

 pices or very steep rocky ascents, sparsely clothed with vegeta- 

 tion. Many of its gullies and ravines are well wooded, and in 

 some of them fine samples of grand African virgin forest are 

 met with. Mr. Whyte's ascent, on the 20th of October, was 

 made up the south-east face of Milanji, over steep grassy hills 

 and across rocky streams, full of large water-worn granite 

 boulders. Further on precipices were encountered, and it was 

 necessary to clamber up, holding on by tufts of grass, roots, 

 and scrub, after which a wooded gorge was entered, and welcome 

 shade was obtained from the forest trees. 



Here an interesting change in the vegetation was at once per- 

 ceptible, the plants of the lower slope being mostly replaced by 

 other species. These in many cases approached the flowers of 

 temperate climes, such as brambles and well-known forms of 

 Papilionacetc and Compositce. Ferns, too, became more nume- 

 rous, and now and again were encountered perfect fairy dells of 

 mosses, Selaginellas, and balsams, with miniature water-falls 

 showering their life-giving spray on the little verdant glades, 

 while overhead hoary lichens and bright festoons of elegant long- 

 tasselled Lycopods hung from the moss-covered trees. After 

 they had passed through some dense thickets of bamboo, and 

 climbed up an ugly barrier of precipitous cliffs, another hour's 

 ascent, the latter part of which was through a steep grassy glen, 

 brought Mr. Whyte and his companions to the highest ridge of 

 Milanji. 



Hence was a splendid view over rolling hills of grassy sward 

 divided by belts of dark-green forest, and the climate was found 

 to be delightfully cool and bracing, with a clear dry atmosphere 

 of about 60" Fahr. Altogether two weeks were spent at three 

 different sites on this high plateau, and good collections of its 

 natural history were made, although rain and mist occasionally 

 interfered with the operations of the naturalists. 



The flora of the mountain proved to be of great interest, 



NO. II 94, VOL. 46] 



being quite distinct from that of the surrounding plains, and 

 even from that of the lower slopes. Tree-ferns were found to 

 attain a great size in the damp, shady forest, and one was 

 measured 30 feet in height and 2 feet in diameter at its base. 

 The display of wild flowers is described as " gorgeous." 

 Creamy- white and yellow helichrysums mingled wiih purple 

 and blue orchids and irises, and graceful snow-white anemones 

 were all blooming in wild profusion, and rearing their heads 

 from a bed of bright green grassy sward. But the most striking 

 botanical feature of the Plateau of Milanji was the cypresses 

 formerly apparently quite abundant, but now confined to a few 

 of the upper ravines and valleys, where the annual bush-fires, 

 which take place in the dry months of August and September, 

 cannot reach them. In some places hundreds of these giant 

 trees thus destroyed lay prostrate, piled one above another, in 

 every stage of destruction. One of these dead conifers was 

 found to measure 140 feet in length and 5 J feet in diameter 

 at 5 feet from its base. The foliage of this cypress is juniper- 

 like. The timber, of a dull reddish-white colour, is of excel- 

 lent quality and easily worked. Ripe cones of this fine tree 

 were procured, and, as stated in a subsequent letter, have already 

 germinated in the experimental garden at Zomba.^ 



The fauna of the mountain was found to be of nearly equal 

 interest to the flora, but in the short space of time available it 

 was not possible to make so nearly a complete collection. 

 Raptorial birds were very scarce, but Passeres were plentiful. 

 The grassy lands of the summits were tenanted by a small dark 

 brown quail, a pipit, two grass-warblers, and the ubiquitous 

 great-billed raven {Corvultur albicollis), which, however, was 

 not so numerous as on the plains below. In the adjoining 

 forest bird-life was abundant. Bul-buls, fly-catchers, warblers, 

 finches, and honey-birds joined in chorus in celebrating the 

 springtime and ne.^ting season, which was then in full progress. 

 Altogether about 200 specimens of birds were obtained. Of 

 mammals few were met with. The beasts of prey consisted of 

 the leopard, the spotted hyaena, the serval, and an ichneumon. 

 Examples of three species of Murida were also obtained, and 

 a little antelope, probably of the genus Neotragu^, was observed, 

 but not procured. A few snakes were likewise met with. 



As regards the question of establishing a sanatorium on the 

 Milanji Plateau, to which special attention had been directed, 

 Mr. Whyte has no hesitation in saying that the climate of this 

 district contrasts very favourably with that of some of the hill- 

 stations in India and Ceylon. The year is pretty equally divided 

 between wet and dry months, the former lasting from November 

 till May, while the other six months are stated to be fine, clear, 

 and bracing, the thermometer at night in the months of May, 

 June, and July occasionally falling below the freezing point. In 

 the month of October the air was found to be delightfully pure 

 and balmy. We believe that steps have already been taken to 

 build a small station on Milanji, but to render this of much use 

 it will be necessary to form a road to it from the falls of the Ruo 

 up the Lutshenya valley. This could be made with fairly good 

 gradients, and would be of great advantage as an outlet for the 

 cypress-timber, which now lies useless and decaying in the 

 forest. 



We are pleased to be able to add that Mr. Whyte's collections 

 above spoken of, along with others from Mount Zomba, have 

 already reached London, and are in the hands of Mr. Sclater, 

 to whom Mr. Johnston has entrusted the task of getting them 

 worked out and described. Mr. Oldfield Thomas has already 

 commenced to determine the mammaIs,Captain Shelley will name 

 the birds, and Mr. Boulenger, it is believed, will undertake the 

 examination of the reptiles and batrachians. The plants will be 

 examined in the Botanical Department of the British Museum, 

 in which institution Mr. H. H. Johnston has directed the first 

 set of specimens in every department to be deposited. The 

 zoological results will be published in the " Proceedings " of 

 the Zoological Society of London. 



OBSERVATIONS OF THE PLANET MARS} 

 T OUGHT to have written to you before on the subject of the 

 -'• planet Mars, which I have been studying for over four 

 months with our great equatorial. My great desire to verify the 



1 Some cones of this supposed "Cypress" have also reached the Botanical 

 Department of the British Museum, and have proved tj belong to a Conifer 

 of the genus Widdringtonia, probably of a new species. But this point 

 cannot be definitely settled until more perfect specimens of the tree have 

 been received. 



^ Letter from M. Perrotin to M. Faye, Coniptes rendiis. September 5. 



