ON SHIELD TUNNELLING IN LOOSE GROUND. 537 



depth that tunnelling became a necessity. The necessity having arisen, it 

 was not shirked, and the work has been saccessfully accomplished. 



In conclusion, the author desires to draw attention to the fact that the 

 condition of unstable equilibrium to which he refers, and which creates 

 most of the difficulties in shield and pneumatic tunnelling, rapidly in- 

 creases with the diameter of the tunnel. He has no doubt whatever 

 that a shield may be constructed in any particular case to meet all the 

 contingencies that can arise ; but it is from works like the Vyrnwy 

 Aqueduct Tunnel under the Mersey, in which the means of meeting 

 difiBcnlties are not sufficiently provided, and where success is nevertheless 

 attained, that the most valuable lessons are to be learnt. 



Report of the Comrrdttee, consisting of Sir W. H. Flower 

 {Chairman)^ Dr. J. Gr. G- arson {Secretary), Dr. J. Beddoe, 

 Greneral A. H. L. Pitt-Rivers, Mr. Francis Gtalton, Dr. E. B. 

 Tylor, and Mr. E. W. Brabrook, appointed for the purpose of 

 editing a new Edition of ' Anthropological Notes and Queries.^ 



The Committee have to report that, in accordance with previous 

 Reports, the Anthropological Institute of Great Britain and Ireland has 

 now completed the task entrusted to it of editing and publishing a second 

 edition, consisting of 500 copies, of ' Notes and Queries on Anthropology,' 

 at a cost of 86L, which includes the cost of partially stereotyping the 

 work for use in a future edition. This expenditure has been met as 

 follows : — Grants from the British Association, 701. ; donation by the late 

 Dr. Muirhead, of Glasgow, 101. ; and the balance by members of the 

 Committee. 



The work as published consists of 242 pages, as against 146 pages in 

 the previous edition ; a double-coloured plate and three other new plates 

 have been specially prepared for this edition, and the illustrations of the 

 former edition have been again used as far as the editors have thought it 

 desirable. All the sections have been thoroughly revised, several of 

 them have been rewritten, others which were left blank in the first edition 

 have been filled up in this, and several new sections have been added. 



As the Committee considered that the object for which the work is 

 published is to enlist the co-operation of as many workei's as possible, as 

 well as to guide and direct them in their observations, the Committee 

 have arranged with the Council of the Anthropological Institute that, 

 notwithstanding its increased size and cost of production, the publishing 

 price of the new edition shall be the same as that of the first edition, 

 namely 5s., and that a discount of Is. &cl. shall be allowed to members of 

 the British Association and Anthropological Institute, making the nett 

 price of the work 3s. 6J. for cash, at the office of the Anthropological 

 Institute, 3 Hanover Square, London, W. 



The Committee consider it very important for the advancement of 

 anthropological science that means should be taken to bring the work 

 under the notice of travellers and others who are willing to undertake 

 anthropological research, and in some cases to make direct application 

 to persons in a position to collect information on various subjects included 

 in the scope of the work. To do this the Council of the Anthropological 

 Institute possess far greater facilities than any committee of the British 



