August 12, 1920] 



NATURE 



759 



Our Astronomical Column. 



An Interesting Meteorite. — Vol. Ivii. of the Pro- 

 ceedings of the United States National Museum con- 

 tains an analysis by Mr. G. P. Merrill of a meteorite 

 that was seen to fall at Cumberland Fells, Kentucky, 

 on April 9, 1919. It is stated that if the object had 

 not been se^n to fall, its meteoric character would 

 not have been suspected. It is a "meteoric breccia 

 composed of fragments of two quite dissimilar stones." 

 The lighter-coloured portion contained 55 per cent, 

 silica, 39 per cent, magnesia, 3 per cent, ferrous oxide, 

 with traces of some seventeen other compounds. The 

 darker portion, which more closely resembles other 

 analysed meteors, contains 42 per cent, silica, 9 }>er 

 cent! ferrous qxide, 28 per cent, magnesia, 12 per 

 cent, iron, etc. "Apparently the admixture of the two 

 kinds of fragments took place prior to the evident 

 cDmpression." 



The author conjectures that it is evidence of the 

 destruction of some pre-existing planet, but the sug- 

 gestion seems more reasonable that it is an earth- 

 born meteor expelled in a mighty eruption in long- 

 past ages. Sir Robert Ball was a strong advocate 

 of the terrestrial origin of meteors, and it appears 

 t<nable in cases where the relative velocitv is not 

 very high. A lunar origin was suggested by Prof. 

 Sampson ; this also is preferable to the postulate of 

 some purely hypothetical planet. 



The Union Observatory, Johannesburg. — Circular 

 Xo. 47 of this observatory contains a search for proper 

 motions by the blink method on two plates taken at 

 Paris in 1887 and 1914. The region is R.A. i8h. 35m., 

 X. deck 31° 10'. The plates have already been 

 measured at Paris, and the region is included in the 

 Greenwich 19 10 Catalogue, so the research was in- 

 tended as a test of the comparative efficiency of the 

 blink method. The result shows that it is undoubtedly 

 the most rapid way of detecting all the displacements, 

 but, of course, the method is purely differential, and 

 absolute motions can be found only by using meridian 

 observations of the reference stars on the plate. In 

 the present case comparison with the Greenwich cata- 

 logue shows that the stellar background is moving 

 3-8" per century towards 113°, so that the blink results 

 are referred to an origin moving in this manner. It 

 is found that each of the three methods of examining 

 the region has revealed some motions not shown 

 by the others, so that they all have their use. Mr. 

 Innes gives the following summary of his results :— 

 Two stars moving more than 20* per century, eight 

 between 20* and 10", seven between 10" and 8", 

 twenty-seven between 8" and 6", and forty-nine 

 (probably incomplete) below 6". 



Galactic Condensation. — The results of an 

 examination of stellar density at different galactic 

 latitudes, derived from plates taken at Sydney, are 

 given in Circular No. 47 of the Union Observatory, 

 Johannesburg. The plates are fairly complete down 

 to magnitude 15 ; there are very few of these faintest 

 stars in the regions remote from the galaxy ; the 

 galactic condensation of the fainter stars is greater 

 than that deduced at Groningen. Incidentally, Mr. 

 Innes criticises Prof..Eddington's statement in "Stellar 

 Movements " that the depth of the stellar system is 

 about three times as great towards the galaxy as 

 towards its poles, and also that the stellar density in 

 the galactic regions is greater than in the polar ones. 

 Mr. Innes shows that, granting, as he does, the latter 

 statement, the ratio of depths becomes very much less 

 than three to one ; in other words, the stellar system 

 is more spherical than previously stated. 



NO. 2650, VOL. 105] 



The British Empire Forestry Conference. 



THE Forestry Commission, constituted in Novem- 

 ber, 1919, has not been long in bringing about 

 what promises to be one of the most important events 

 in the history of forestry in the British Empire. We 

 allude to tlie British Empire Forestry Conference 

 which, with intervals for visits to certain selected 

 forest areas in England and Scotland, held its sittings 

 in London on July 7-22 under the chairmanship of 

 Lord Lovat. The delegates included representatives 

 from the United Kingdom, Australia, Canada, India, 

 Newfoundland, New Zealand, South Africa, the 

 Sudan, and most of the Crown Colonies. The 

 main objects of the conference were to bring 

 together such information as exists at present regard- 

 ing the forest resources of the Empire, and to devise 

 means of forming a more accurate estimate of these 

 resources and of developing them to the utmost ; to 

 focus attention on the necessity for a more rational 

 forest policy in the various parts of the Empire ; to 

 bring to light some of the more salient problems con- 

 nected with technical forestry; and to consider 

 certain important questions relating to forestry educa- 

 tion and research. 



No more opportune time could have been selected 

 for such a conference. Of the many forcible lessons 

 taught us bv the Great War there are few which 

 require to be taken more to heart than the lesson 

 taught us in regard to the maintenance of our timber 

 supplies. The view once held, that the timber 

 resources of the Empire are inexhaustible, is no longer 

 tenable, for we are already faced with a probable 

 world-shortage of timber which will become more and 

 more acute if steps are not taken to prevent reckless 

 waste and to ensure that production keeps pace with 

 exploitation. In the affairs of our Empire the 

 scientific aspect of forestrv has been too long relegated 

 to the background, largely owing to- misapprehension 

 as to its true aims. For forestry, no less than agri- 

 culture, is an industry based on the productive 

 capacitv of the land, with this important difference : 

 that whereas agricultural crops are harvested within 

 a year, forest crops may take a century or more to 

 mature. Hence in forestrv, far more than in agri- 

 culture, the State must take a direct interest in the 

 growing of the crops concerned, for the success of 

 which continuity of management based on scientific 

 principles is the keynote. 



.Among the most important proposals approved of 

 bv the conference was that relating to the formation 

 of an Imperial Forestry Bureau to be located in 

 London. This Bureau, constituted somewhat on the 

 lines of the Imperial Mineral Resources Bureau, 

 would act as a clearing-house of information on all 

 subjects connected with forestry and forest products. 

 It would undertake to collect, co-ordinate, and dis- 

 seminate information on forest education, research, 

 policy and administration, and the resources, utilisa- 

 tion, consumption, and requirements of timber and 

 other forest products. In this way the Bureau 

 cannot fail to prove a valuable link in forest matters 

 between the various parts of the Empire. 



.\mong the more important specific questions which 

 it is hoped the Bureau will lose no time in takinp- up 

 are the standardisation of technical terms used in 

 forestrv and the correct identification of timbers in 

 commercial use. with the standardisation of their 

 trade names so far as this is posstt)le. 



The question of forest research work was fully 

 considered. The conference held that this work, for 

 various reasons, is primarily the concern of the State. 

 Speaking generally, forest research is divisible into 

 two main branches : (i) that dealing with the grow- 



