1 64 SCIENCE PROGRESS. 



of which Lord Balfour of Burleigh was Chairman, and of 

 which Professor Dewar was a member. 



The Royal Institution has also for nearly three-quarters 

 of a century been prominently connected with the investiga- 

 tion and improvement of the Metropolitan Water Supply ; 

 no less than four of our Professors of Chemistry having 

 been successively engaged in this work, viz., Professors 

 Brande, Odling, Dewar, and myself, whilst three of them 

 have been members of the Royal Commissions just 

 mentioned. I may therefore perhaps be excused for 

 accepting the invitation of our Secretary to bring the 

 subject under your notice for the third time. 



On the present occasion I propose to consider it from 

 three points of view, viz., the past, the present and the 

 future ; and, for reasons which will appear hereafter, I shall 

 divide the past from the present at, or about, the year 1883, 

 and will not go back farther than the year 1828, when Dr. 

 Brande, Professor of Chemistry in the Royal Institution ; 

 Mr. Telford, the celebrated engineer ; and Dr. Roget, 

 Secretary of the Royal Society were appointed a Royal 

 Commission to inquire into the quality and salubrity of the 

 water supplied to the Metropolis. 



The Commissioners made careful examinations and 

 analyses, and reported as follows : " We are of opinion that 

 the present state of the supply of water to the Metropolis 

 is susceptible of, and requires, improvement ; that many of 

 the complaints respecting the quality of the water are well 

 founded, and that it ought to be derived from other sources 

 than those now resorted to, and guarded by such restrict- 

 tions as shall at all times ensure its cleanliness and purity. 

 (At this time the water was pumped from the Thames 

 between London Bridge and Battersea.) To obtain an 

 effective supply of clear water free from insects and all 

 suspended matter, we have taken into consideration various 

 plans of filtering the river water through beds of sand and 

 other materials ; and considering this, on many accounts, as a 

 very important object, we are glad to find that it is perfectly 

 possible to filter the whole supply, and this within such 

 limits, in point of expense, as that no serious objection can 



