Macnish is the most liberal modern writer I am acquainted with, in his allowance of time for sleep. Speaking of the wants of adults he says--"No person who passes only eight hours in bed can be said to waste his time in sleep." Yet he obviously contradicts himself on the very same page; for he says expressly, that when a person is young, strong and healthy, an hour or two less may be sufficient. But an hour or two less than eight hours reduces the amount to seven or six hours. And taking the whole period of life, to which he probably refers--say from eighteen to forty--into consideration, there is a very considerable difference between six hours and eight hours a day. If six hours are "sufficient," it cannot be right to sleep eight hours. Let us here make a few estimates. If six hours are sufficient for sleep between the ages of eighteen and forty, he who sleeps eight hours a day, actually loses 16,060 hours--equal to nearly two whole years of life, or about two years and three quarters of time in which we are usually awake. This, in the meridian of life, is not a small waste. Permit it to every person now in the United States, and the sum total of wasted time to a single generation, would be 25,649,098 years--equal to the average duration of the lives of 854,970 persons. The value of this time, as a commodity in the market, at a low estimate--only forty dollars a year--would be over A THOUSAND MILLIONS of DOLLARS! And its value, for the purposes of mental and moral improvement, cannot be estimated except in ETERNITY! Every young mother must derive from these considerations a motive to discourage all unnecessary waste of time in sleep; while no one, as I trust, will forget that to sleep too little is also dangerous to health, and prejudicial to the general happiness. CHAPTER XV. EARLY RISING. All children naturally early risers. Evils of sitting up late at night. Excitements in the evening. The morning, by its beauties, invites us abroad. Example of parents. Forbidding children to rise early. Keeping them out of the way. How many are burnt up by parental neglect. "Lecturing" them. What is an early hour? Some writer--I do not recollect who--has said that all children are naturally early risers. And I cannot help coming to the same conclusion. That they are not so, is no more proved from the fact that as things now are they are generally found addicted to the contrary habit, than the very general neglect of milk among the higher classes of our citizens, proves that they have not a natural relish for it--when every one knows that at our first setting out in life, milk is, almost without exception, the sole article of human sustenance.