260 



NATURE 



[Jan. 15, 1880 



Secondly, it is unfortunate that naturalists were not 

 likewise sent to Oahu, in the Sandwich Islands, where 

 there was likewise an astronomical station in 1874. The 

 Sandwich Islands, as was pointed out by our correspon- 

 dent in 1870, are the seat of a most peculiar indigenous 

 flora and fauna, which is now fast perishing beneath 

 the assaults of European weeds and animals introduced 

 from other countries. Dr. Finsch, who was lately at 

 Honolulu on his way to the Northern Pacific, tells us 

 (Ibis, 18S0, p. 79) that during a week's stay in that city 

 and its vicinity, he saw no birds except introduced species, 

 and had to go far into the interior to obtain examples of 

 the indigenous Avi-fauna, and that the '' native forests are 

 going in the same way." It is a great misfortune, then, 

 that this should happen before we have any good account 

 of this peculiar flora and fauna which rivals in eccentricity 

 even that of the Galepagos. And as another Transit 

 occurs in 1882, we trust that should our astronomers 

 again visit any one of the Sandwich Islands group, a staff 

 of efficient naturalists will be sent in their company. 



ARTIFICIAL DIAMONDS 



UNDER the heading of "The Crystallisation of 

 Carbon" Mr. Crookes writes as follows in the last 

 number of the Chemical News : — 



Since sending the telegram ' announcing that carbon 

 crystals, apparently diamond, could without difficulty be 

 produced from any carbon compound, Mr. Mactear has 

 sent me several specimens of his supposed artificial 

 diamond. He has also called upon me with other speci- 

 mens, and has explained the whole process by which he 

 obtains such remarkable results. As, however, he has 

 sent to the Royal Society a paper which will probably be 

 read in the course of a week or two, I am not yet at liberty 

 to give details of the process. 



The general character of the specimens now in my 

 possession may be described as irregularly shaped masses 

 from 1 mm. downwards in diameter, with rounded angles, 

 and showing no definite crystalline appearance. They 

 are whitish looking, translucent, and as a rule lustreless ; 

 many pieces are almost spherical and appear like frag- 

 ments of corundum which have been water worn. Amongst 

 these are perfectly clear fragments larger in size, some 

 being 3 or 4 mm. across, having a conchoidal fracture 

 exactly like glass. 



In a paper " On Molecular Physics in High Vacua," 

 read before the Royal Society in March last, and now 

 being published in the Philosophical Transactions, I re- 

 ferred to the remarkable power possessed by the molecu- 

 lar rays in a high vacuum of causing phosphorescence in 

 bodies on which they fall, and I remarked that the only 

 body which surpassed Becquerel's luminous sulphides 

 both in brilliancy and variety of colour is the diamond. 

 Most of these gems, whether cut or in the rough, when 

 coming from the South African fields, phosphoresce of a 

 brilliant light blue colour. Diamonds from Brazil shine 

 with different colours, such as bright blue, pale blue, 

 apricot, red, yellowish green, orange, and light green. A 

 beautiful collection of diamond crystals, kindly lent me 

 by Prof. Maskelyne, phosphoresced with nearly all the 

 colours of the rainbow, the different faces glowing with 

 different shades of colour. On receiving the specimens 

 from Mr. Mactear, I immediately submitted them to the 

 molecular discharge. The following are the results I 

 have at present obtained : — 



In a high vacuum the specimens phosphoresce brightly 

 of different colours — pale blue, orange, apricot, and 

 yellowish green. The clear glassy fragments are also 

 phosphorescent. The appearance of the phosphorescence 

 is very similar to that shown by small, rough diamonds 

 from Brazil, called in the trade " Boart ; " indeed, had 

 I not known the history of the fragments in my tube, I 

 1 Chemical Neva, vol. xl. p. 306 (December 26, 1S79). 



should, from their appearance, have said that they were 

 small fragments of Brazilian Boart. 



The opaque rounded appearanee of the fragments is 

 unlike that of the natural diamond, but by heating a 

 rough diamond before the blowpipe until it has partly 

 burnt away, it assumes a very similar appearance to that 

 of Mr. Mactear's crystals, and it is therefore not unlikely, 

 from their mode of preparation, that these crystals have 

 undergone partial combustion after their formation — a 

 fact which would explain this difference in appearance. 

 Other specimens having been placed by Mr. Mactear in 

 competent hands, with a view of determining their hard- 

 ness and chemical properties, I have refrained from 

 making experiments in this direction. W. C. 



We append a letter on the subject from Prof. Maskelyne 

 in the Times of the 8th inst. : — 



As I know that a portion of the public is very much 

 interested in the diamond question, and in the result of the 

 interview Mr. Mactear announced that he and I were to 

 have in connection with it, I think, perhaps,- it will be 

 well to say that I have had the pleasure of working with 

 that gentleman many hours yesterday and to-day, and 

 that our results so far convince me that, while my own 

 conclusions, as announced in the Times, are borne out as 

 regards at least the portion of the substances on which I 

 worked, there are other portions of those substances that 

 differ from these in properties and still require investiga- 

 tion ; that, in fact, the material is a mixture of different 

 bodies. When I say that I have as yet no evidence of 

 the existence of crystalline carbon, whether as diamonds 

 or in some other condition, among these bodies, I feel 

 that Mr. Mactear makes a reasonable request of me in 

 asking that I should invite a suspension of opinion 

 regarding a discovery he believes that he has made. A 

 portion of the material he has produced is very hard, and, 

 I believe, bears out his claim to have scratched topaz and 

 sapphire. Mr. Mactear wishes me to add that the 

 diamond has been also abraded by his product and to 

 inclose to you a certificate to that effect. Mr. Mactear 

 wishes me also to state that he claims simply to have 

 produced a crystalline form of carbon irrespective of the 

 question of whether this is the diamond. 



I am, Sir, your obedient servant, 



Nevil Stokv-Maskelync. 



British Museum, January 7 



We may state that in the Times of the same date is a 

 certificate from Mr. L. Boston, of Glasgow, that he has 

 been able ''to scratch a diamond and to engrave two 

 rubies, two sapphires, an amethyst, and a cairngorm" 

 with Mr. Mactear's "crystallised carbon sand." 



THE "TIMES" ON BRITISH BIRDS 



NATURALISTS live a life of surprises, but the sur- 

 prise with which ornithologists must have one day- 

 last week received certain positive assurances of the 

 leading journal would surely overstep the bounds of 

 ordinary astonishment. We have, no doubt, been passing 

 through a " silly season " of unwonted severity, as the 

 morris-dance of late performed by many of the pseudo- 

 ornithological correspondents of the Times proves ; but 

 a recent leading article in that journal eclipses all else 

 that it has published on the subject. 



After declaring that " our birds are the glory of the 

 land," and piously ascribing that glory to the upper 

 regions, the writer goes on to compare England with 

 France in the matter of its birds, saying, of course, 

 nothing that was not quite well known before, except the 

 extraordinary statement that "France has produced 

 ornithologists, but they have had to leave her shores." 

 The meaning of this is entirely beyond us, for ever) one 

 knows who cares to know that France now possesses a 

 large number of ornithologists — and one indeed, M. 



