ON BIOLOGICAL STATION— OVERSTRAIN KD MATERIALS. 263 



Fresh-Water Biological Station. — Report of the Committee (Prof. 

 F. E. Fritsch, Chairman; Prof. F. Balfour Browne, Secretary; 

 Dr. B. M. Griffiths, Dr. Gurney, Prof. H. S. Holden, Dr. W. H. 

 Pearsall, Dr. B. S. Russell, Mr. J. T. Saunders) appointed to 

 consider the means to he adopted for the establishment of a suitably 

 equipped Fresh-water Biological Station. 



This Committee has held three meetings for the consideration of the object for 

 which it was appointed, and it has decided that the best means for attaining that 

 object is the formation of a British Fresh- water Biological Asfsociation. 



Steps have now been taken by those interested in the subject towards the forma- 

 tion of such an Association, which, however, is outside the work of this committee, 

 which has now completed its work. 



Stresses in Overstrained Materials. — Report of the Committee 

 (Sir Henry Fowler, Chctirman; Mr. J. G.'Docherty, Secretary ; 

 Prof. G. Cook, Prof. B. P. Haigh, Mr. J. S. Wilson). 



The first meetings of the Committee were devoted to general discussions of the 

 problem, and the best method of investigation. 



The following programme of work was finally approved, and is in progress : — 



1. An investigation of the stress- strain relation beyond the yield point, and an 

 examination of any work already done on this subject. 



2. A theoretical investigation of the stress and strain distribution beyond the 

 clastic hmit or yield point, in bodies of relatively simple geometrical form, e.g. 

 simple beams, thick tubes, &c. 



3. Experimental verification of the above examples. 



4. A paper on the effect of overstrain in producing ' triple tensile stress ' or 

 ' fluid tension ' (i.e. the reverse of fluid pressure), and the effect of such stress in 

 producing fracture. 



5. General papers discussing the application of the foregoing theories and experi- 

 ments to practical problems in the light of experience. 



The committee have co-opted Prof. G. Cook, D.Sc, and he has expressed his 

 willingness to serve. 



The committee ask to be reappointed for another year, as the work is stiU in its 

 initial stages. The terms of reference were wide, and much time was spent before 

 the above programme was approved. 



No part of the grant has been spent this year, but it is hoped that the grant may 

 be continued next year. 



