278 REPORTS ON THE STATE OF SCIENCE, ETC. 



Chemical Analysis of Upland Bog Waters. — Report of Committee 

 (Prof. J. H. Priestley, Clmirman ; Mr. A. Malins Smith, Secretary ; 

 Dr. B. M. Griffiths, Dr. E. K. Rideal). 



The figures of the complete analyses of the water of Miles Rough bog, Bradford, 

 taken in April and June, 1928, showed no significant differences between inlet and 

 outlet except in nitrate content. The complete analysis of the water of Heather 

 Glen bog, near Bingley, taken in Ma}', 1929, gave a similar result. No further water 

 analyses could be made in 1929 owing to the drought. 



As the results of the previous complete analyses had pointed to nitrate, as the 

 significant variable, the analyses of 1930 were confined to this constituent, except that 

 in April figures for Calcium were also obtained, as it was deemed of possible significance. 

 The results of two sets of analyses, taken in April and June respectively, point to the 

 importance of nitrate supply in algal growth. In April the freely inflowing water is 

 charged with considerable amounts of nitrate, and this is the time of the greatest 

 growth of algae. In June the incoming supply is cut off and the nitrate of the water 

 standing in the bog is reduced to a very low figure. This is followed by the lowest 

 ebb of algal life. The general indications, therefore, are that nitrate is the limiting 

 factor in the growth of algae in this situation. Details will be given in a separate 

 communication. 



The grant is now expended, and as the two most significant periods only of the 

 algal year have been investigated, it would be useful to supplement previous work by 

 nitrate analyses in October and February. It is, therefore, requested that the Com- 

 mittee be reappointed with a grant of ten pounds. 



I 



