Before transmitting the returns, you are to read them at a meeting of the Board of Guardians, acquaint them with the answers, and annex any further information which they may be enabled to communicate in aid of the inquiry. Signed, by Order of the Board, EDWIN CHADWICK, _Secretary_. To the Clerk to the Board of Guardians. 3.—_Circular Letter of Inquiry to the Medical Officers of the Unions in England and Wales, transmitted to them, with Forms of Return, through the Clerks to the Guardians._ Poor Law Commission Office, Somerset House, 12th November, 1839. Sir,—With the view of ascertaining the extent of the existence of circumstances promoting the prevalence of contagious and infectious diseases described in the reports referred to in the Order of the House of Lords, set forth in the letter from Lord John Russell, a copy of which is hereto annexed, you are requested to fill from the medical relief Lists the enclosed returns, and transmit them to the clerk of the union, with such observations as occur to you thereon. You will observe that the object of the Commissioners is to ascertain the existence and extent of the visible and removable agencies promoting the prevalence of such diseases as are commonly found connected with the defects in the situation and structure or internal economy of the residences of the labouring classes. The attention of the physicians who drew reports on the state of the metropolis was almost exclusively directed to the causes affecting the prevalence of various forms of _continued fever_, arranged under distinguishing names adopted by nosological writers: but in rural districts the prevalence of ague, and of small-pox, and scarlet fever, may be worthy of notice when the causes promoting their prevalence appear removable. You will, in your observations on the class of cases returned, note the situation, character and quality of the tenements in which the diseases have occurred;—whether they are situated in a neighbourhood habitually infected with malaria;—whether there are occasional causes of malaria, such as floods, &c.; and in such cases, whether you have any suggestions to make as to the best means of diminishing the evil;—whether they are drained or undrained, whether tight or otherwise;—whether there are good means of securing ventilation with a due regard to warmth;—whether there are accumulations of filth, and if so, whether they are ascribable to the slovenly or indolent habits of the inmates, or to the want of proper receptacles for refuse;—whether the occurrence of disease amidst this part of the population is regular or otherwise, and what are the seasons at which it appears, and its characteristics.