(A). - Letter by the Author published in the "Times," August 13 th, 1869.

Sir, - The London season is over once more, and every one is hurrying to get a dash of sea water or of mountain air, before returning to London work. Brain-fag, nervous exhaustion and worry are the universal complaints; and who can wonder at it? For where and when in this great city, I should like to be told, can any one secure six hours of undisturbed sleep?

If insanity increases, if doctors are more busy every year with diseases of the nervous system, if men and women wear out faster and faster, who can wonder, if he will take the trouble to consider how utterly our municipal arrangements ignore the necessity for sleep?

It is time, indeed, that we turned our attention to this vital question, upon which hangs not only the comfort and happiness of our best men and women of the day, but the actual value of their mental work, the continued sanity of their minds, and the mental calibre of their progeny. I am not the only member of my profession who has long desired to bring this matter into public notice; far otherwise. Your columns might easily be filled day by day with the sore experiences of medical men on this point. But I see the evil increasing year by year, and I cannot longer keep silent when I see "holiday tasks" set to thinking men, to rob them of the only chance they had left of recreation and rest.

If some of us are to be doomed to spend the recess in digesting Education Bills, and in speculations on the value of clipped sovereigns, at least let some others of us consider the value of a little sleep.

This is a very simple question, and the evil appears to be susceptible of a simple remedy. It is a question of police; and attention being once prominently called to its importance, there can be no excuse for its being longer neglected. The police should be made to keep our streets quiet during certain hours of the night. No attempt at this is made at present. The night policemen walk tacitly up and down, while every house in a street is being roused by the most abominable noises, without making the slightest attempt at checking them. It might not unfairly be asked that people should have a chance of sleeping from twelve o'clock till eight; but, in the name of all that is sane, let them have the possibility of sleeping from two o'clock till eight.

There is no such chance now. No one interferes to stop any amount of noise in the night and early morning. A party of cats may hold an uproarious concert in the middle of the road without even a "hiss" from the policeman to disperse them. Two "cabbies" may career down the opposite gutters, and hold conversation across the road at the top of their voices. A train of scavengers' carts may be driven down the streets, rumbling like thunder, while the driver in the last cart holloas his jokes to the man in the front. In some districts it is thought necessary to create the most infernal noise about five o'clock in the morning by setting a host of garrulous old men to scrape and stone the roads at that pleasant hour. On Sunday mornings the paper boys are allowed to bawl with all their might. At any hour of the night, a fool in love with a concertina may disturb a whole neighbourhood with the noise he pleases to think music; and no interruption is given to any number of drunken rollickers who choose to sing and holloa up and down our streets and squares. I have said nothing of the early organ-grinders, collectors of hares' and rabbits' skins, sellers of water-cresses, the inevitable dustman, the rows attendant upon balls and receptions, or a hundred other sleep preventers, too painfully familiar to those who turn into their beds between twelve and three o'clock in the morning, their brains fagged and excited by work - parliamentary, scientific, judicial, professional, it matters not which, or even by those unavoidable and wearying pursuits of social life which we call "society." Of the sick I dare not even speak, for to them this everlasting noise is simply murder. But for those in ordinary health, for those who are doing the brainwork of the nation, I ask for some chance of at least six hours quiet sleep out of twenty-four. Even this moderate allowance might suffice to restore the wear and tear of the day and refresh the spirits for the ever recurring fight. But such sleep is utterly impossible, as a rule, in the present state of things, and hence the yearly increasing decay of mental and nervous health.

It needs but your aid, Sir, to procure a remedy. With proper police regulations the noisiest place in London can be kept comparatively quiet, as the citizens have shown in the main thoroughfare through their new meat market in Smithfield. There a couple of policemen, properly instructed, stop all unpleasant noise. I trust, then, that before London assembles again for work, some steps may have been taken to give us quiet streets for at least six hours out of the twenty-four.

(B.) - Leader from the "Times" referring to the above letter.

Our correspondent 'M.D.' may, we think, claim the credit of having suggested, or at least drawn public attention to, a new remedy for a very old and common complaint. The complaint cannot, indeed, be altogether got rid of without revolutionizing our whole system of modern life, for it simply amounts to this - that men now-a-days work so hard, and live in such a constant whirl of excitement, that neither body nor mind gets sufficient recreation or rest. The mind is naturally the greater sufferer, for the obvious reason that it may be kept almost incessantly in harness, and may be working its very hardest, while the body comfortably stretched on bed or sofa, is enjoying luxurious repose. It is scarcely too much to say, for instance, that men of anxious temperament engaged in commercial speculations, during critical times, do not, from the moment they open their eyes in the morning to the moment, they close them at night, know what it is to have ten minutes altogether free from absorbing calculations, how to avoid this possible piece of bad luck or turn good luck to the best advantage. Even when they try to banish these exciting topics - an effort, however, which over-anxious minds seldom make very strenuously - their brain, nevertheless, will sometimes work in spite of them. And what happens to them happens, if in less degree, to nearly all who have to win their bread in professions and occupations where competition is keen. Hence it is, as 'M.D.' points out, that we see what are vaguely called 'nervous complaints' steadily on the increase, often leading, if they are not at once taken vigorously in hand, to confirmed ill-health, and sometimes even to insanity. 'It is time,' he declares, 'that we turned our attention to this vital question, upon which hang not only the comfort and happiness of our best men and women of the day, but the actual value of their mental work, the continued sanity of their minds, and the mental calibre of their offspring.'