ON THE TREATMENT AND UTILIZATION OF SEWAGE. 
433 
with Portland cement into a mass which is moulded to the required shape, allowed 
to dry by exposure to the air, and then hardened by immersion in the bath of sili¬ 
cate. The stone so made is said to wear longer than the best Yorkshire flag¬ 
ging. “ Petrified concrete’’ is also specially applicable to the construction of 
cornices, copings, etc. Water cisterns, sinks, tanks, and even water pipes are 
made of it. Being quite impervious to moisture, it resists the frost well, and 
time rather increases its hardness than otherwise. 
COMMITTEE OF THE BRITISH ASSOCIATION ON THE TREATMENT 
AND UTILIZATION OF SEWAGE. 
22, Whitehall Place , London , S. W. 
November 30 th, 1869. 
Sir.—I have the honour to inform you that, last year, at the meeting of the British 
Association at Norwich, a committee was appointed to report on the treatment and 
utilization of sewage. In the first instance, a grant of £10 was placed at the disposal of 
the committee, with which to defray the cost of printing and postage incidental to the 
collection of preliminary statistical information. Through the kindness of her Ma¬ 
jesty’s Government, the committee was enabled to obtain reports respecting the methods 
of dealing with town refuse practised in most civilized countries, and that information 
has now been collected in a more complete form than hitherto existed in any country. 
This preliminary work being completed, the committee was reappointed at the meet¬ 
ing of the British Association this year at Exeter, and the inquiry was considered to 
present such important features of social and scientific interest, that the sum of £50 was 
voted towards enabling the committee to enter more fully and practically upon the in¬ 
vestigation of this subject. The British Association, being a purely scientific body, has 
not at its disposal funds which would be adequate or applicable for the full prosecution 
of this very large and pressingly-important inquiry. The committee nevertheless desires 
to take advantage of the opportunity created by the British Association, to investigate 
the entire subject in all its bearings—whether chemical, physiological, or engineer¬ 
ing, sanitary, municipal, or agricultural—and in a manner worthy of the body they 
represent. 
It is unnecessary to point out the enormous importance, especially at the present 
time, of a full and complete investigation of this question by the light of the knowledge 
and experience now gained in the several departments above alluded to; but, properly 
to carry out such an inquiry with a practical end, numerous observations, gaugings, and 
experiments, aided by simultaneous analyses, are essential; and these cannot be accom¬ 
plished, especially the analyses, without the continued aid of efficient and therefore 
highly-paid assistants. Moreover, from time to time it may be necessary for the com¬ 
mittee to purchase expensive apparatus, and to subject various inventions and processes 
to a thorough and complete test; for it is the desire of the committee, not only to ascer¬ 
tain, as far as possible, the causes of the sanitary inefficiency of existing works ; but 
also to inquire into every suggestion which affords promise of practical utility, in order 
that this investigation may be searching, the report practical, and any recommendations 
that may be made authoritative. 
It is the wish of the several members of the committee to devote, to the utmost of 
their ability, their personal attention to the work thus sketched out; but the expenses 
absolutely necessary to enable them to conduct so extended an inquiry cannot but be 
very heavy, and, unless they are able to secure an adequate fund, they must abandon 
the attempt to investigate the subject in this broad and comprehensive manner. How¬ 
ever, since there is no subject of greater practical and social importance to the public 
generally, and thus to the various municipal authorities and other governing bodies 
throughout the country, it is believed that many will share the opinion expressed at the 
recent meeting of the British Association at Exeter, that the existence of this com¬ 
mittee affords a specially favourable opportunity for such a wide inquiry, and for that 
reason its members confidently appeal to those authorities who are officially interested 
in the subject to supply the funds necessary for the investigation. 
I am therefore desired to request that you will kindly submit this letter to the body 
