90 Notes and Comments. 



imagination, have had great influence in encouraging workers 

 and popularising • geological studies. The members of the 

 Committee feel confident that a large number of persons and 

 societies will desire to join in this tribute of appreciation 

 and regard. Cheques may be crossed and made payable to the 

 Hon. Treasurer, J. E. Bedford, Esq., F.G.S., and should be 

 sent to him at Arncliffe, Shire Oak Road, Headingley, Leeds. 

 It is intended that the presentation to Professor Kendall shall 

 include an address with the names of the subscribers, but the 

 amounts of contributions will be regarded as confidential by 

 the Committee.' 



PURE ' BLUE JOHN.' 



We learn from The Quarry that the recently discovered 

 ' Troke Cliffe ' Mine is the only one in the world producing 

 almost perfect Blue John Fluorspar. Apart from the ordinary 

 commercial quality so largely used by steel works, the really 

 choice specimens are used for turning and ornamental purposes. 

 Thus the material is a very valuable one. An analysis of the 

 product from the mine proved the same to be practically 

 pure ; it contains 97*92 per cent, of calcium fluoride and 0.6 

 per cent, of calcium carbonate. The outside workings of the 

 mine are in quarry form, and there is a most unusual face of 

 solid Blue John variety of fluorspar. The increasing output 

 from this mine will do much to relieve the present shortage 

 of this material, and progress within the last three months 

 has been so rapid that a transport tramway has had to be laid 

 down. Within a short time there will be a large number of 

 men. engaged on a workable face of some 30 to 40 feet. 

 Developments are being planned by the owners to increase 

 the output considerably, and only the highest grade of Blue 

 John will be placed on the market. 



BUREAU OF BIO-TECHNOLOGY. 



The Bureau of Bio-Technology, Queen Square, Leeds, 

 issues a useful Bulletin, parts i and 2 of which are before us. 

 Among the papers are ' Microscopy and Biology in Industry,' 

 ' System in the Nomenclature of the Bacteria,' ' The Destruc- 

 tion of Stored Grain by Trogoderma khapra Arrow, a new pest 

 in Great Britain,' all by F. A. Mason; 'An Investigation of 

 the Causes of " Run " Pelts in the Sweating Process,' by 

 P. Hampshire. There are also interesting ' Notes from the 

 Laboratories.' 



A NEW ANTIQUARIAN JOURN.^L. 



A valuable new magazine made its appearance in The 

 Antiquaries' Journal, being the journal of the Society of 

 Anti(iuaries of London. It is quarterly, issued at the Oxford 

 University Press, at 5s., and takes the place of the Society's 

 Annual ' Proceedings,' which therefore cease. The journal is 



