I think from what I have said, this can hardly be regarded an unnecessary work; but should this be deemed impracticable—though I cannot see how it can be—I would suggest the desirability of all water used for drinking and culinary purposes being filtered; that is, where there is any suspicion of decomposed organic matter in the cistern, tub, &c. Any working man with ordinary ingenuity might contrive to filter his water through a little sand and vegetable charcoal. I know of no filters that could be purchased for 1s. 6d. or 2s., which I presume is about the extent that many of the poor in my district could go to. A rough-and-ready filter might be made out of a large flower-pot, the hole at the bottom being plugged up with sponge, and then a layer of charcoal and another layer of sand. The water would percolate through these substances, and be as clean and pure as the water from the mountain rill. The flowerpot might be suspended over another vessel, which would receive the pure water, or it might be so placed as to stand on two pieces of wood over another vessel. There are many ways of filtering water, but it is only my object to show how simple, inexpensive it is, and that it is within the means of the poorest to protect themselves from the disastrous effects of impure water, at a little cost of labour and at a still less cost of money. There can be no doubt that water is not appreciated as a sanitary agent. This may arise either from ignorance or indifference; but, after what has been said, I trust that the apathetic neglect of the primary laws of health, and that blind confidence in an overruling Providence, that in the end all will come well—may vanish as the baseless fabric of a vision. It is in vain to call upon the local authorities to supply a larger quantity of water, if we either from ignorance or indolence neglect to use it. It is in vain to call upon landlords to build houses properly drained and ventilated if those who take them are ignorant and indifferent to the value of fresh air and good drainage. Dirt is allowed to begrime the walls, so as to render it difficult to tell what the original colour was; in a word, many of the rooms in George-street, Charles-street, Little Bell-street, Little Church-street, East-cottages, and many others in my district, are so neglected by the tenants as to become neither more nor less than fever nests. Soap and water and white lime, to judge from the condition of very many of the rooms in my district, might be as expensive a luxury as salt in Abyssinia. Every traveller that visits tropical countries is sure to complain of the annoyance and inconvenience of mosquitoes, and I am equally sure that every visitor to the dwellings of the poor in the locality I have indicated might reasonably complain of the visitors, who, on account of the dirt, have taken up a permanent residence, but whose name it is not deemed polite to mention, though as far as number is concerned they might be justly termed legion.