1866. | Sewage and Sewerage. 193 
meadow or as weeds in the ditch we trust for disinfection, since, 
besides beg thus unsightly and unsavoury to man, they would be 
injurious and indeed fatal to the plants and their functions. And 
to pipes and pumping they are as obnoxious as they are to living 
beings. Filters consequently of one kind or another, either coarse 
ones of wicker-work, or more complex combinations of sand, gravel, 
and ashes, alternating with strata of hurdle-work, are employed to 
free sewage from these troublesome constituents. Of the coarser 
kind little need be said, beyond suggesting, that a rapid flow of the 
main drainage contents over an artificially roughened bottom might 
by the attrition and contrition of the matters referred to, set free at 
once into solution, or at all events ito suspension, much that 
might otherwise remain for a long time clogging the filtermg hurdles 
and being otherwise offensive and noxious. The more complex 
kinds are well described and figured both by the Barrack Com- 
missioners (‘ Report,’ p. 86), and by Mr. Menzies (p. 23); and from 
the latter gentleman we learn the interesting fact, that we owe the 
suggestion of the principle of upward filtration to the ingenuity and 
insight of the late Prmce Consort. Filters, whether simple or 
complex, are lable to displacement and derangement by the sudden 
influx of storm-water, as well as to clogging by any sudden afflux 
of the solids of sewage; and on these grounds filters, together with 
filtering beds, should always be provided in duplicate, side by side, 
as in the figure.given by the Barrack Commissioners. 
Much of the labour which we should otherwise have had to 
impose upon ourselves and our readers, in estimating the merits and 
claims of the several works, the titles of which stand at the head of 
this article, has been saved to us by the judicious and well-written 
pamphlet of Dr. Child. The title of his pamphlet is modest, and 
we can assure all persons who may wish to gain a knowledge of 
this subject and its literature, on the easy terms of reading an 
agreeably written tract, that they will find the performance to 
exceed by much the promise of the title-page. 
As it is the fashion in England—a country where the Govern- 
ment makes its presence to be seen and felt in no other ways than 
by the penny post and the policemen in our streets and areae—to 
depreciate and vilipend all else that wears the Government stamp, 
we ourselves, having, and indeed desiring, no other relation with 
the Government than that which the former of the two functionaries 
just specified sets up between us, think it right to set ourselves 
against the prevailing fashion, and to say something in praise 
of the much and most unjustly abused Blue Books. We are 
glad to observe that Dr. Parkes (p. 266 7. ¢.) makes no secret 
of the extent of his obligations to the Barrack Commissioners of 
1861; and, being well able to stand upon his own merits is not 
niggard in his bestowal of praise on others. In days, however, 
