ical. A weight is a much better device, and yields a large per cent, of the power expended in raising it when it falls. Such an arrangement is, however, a thoroughly impracticable one, as a simple calculation will show. It takes about four hundred foot-pounds per minute to drive a sewing-machine, so that to run one an hour a weight of a fifth of a ton would have to fall sixty feet. The only practicable way of utilizing gravity for motive power is by the water-wheel, where the weight can fall continually, and the cost of raising it again is a minimum.
By T. LAUDER BRUNTON, M.D., F.R.S.
TO most men who are engaged in intellectual work, an autumn holiday has become a matter of necessity, and is not to be regarded as a mere luxury. During eleven months of the year many who are engaged in brain-work systematically overtax themselves, trusting to the month's holiday to bring them again into proper working order. Formerly this was not the case. Men seemed to be able to go on, not only month after month, but year after year, without any vacation at all. The circumstances under which they lived were different from those which exist now. The very means which facilitate our holidays}}the network of railways which puts us into complete and easy communication with any part of the Continent of Europe, or the quick ocean-steamers which enable us to enjoy half of a six weeks' holiday on the other side of the Atlantic, as well as the telegraphic communications which will warn us in a moment, even at the most distant point of our travels, of any urgent necessity for an immediate return—all these are the very means which increase our labor during the greater part of the year. We live at high pressure; letters and telegrams keep us constantly on the qui vive; express trains hurry us miles away from home in the morning and back again in the evening, and the pressure of competition is so great that few men can afford either to take their work easily or to modify the constant strain of it by breaks of a day or two at a time. Wearied and exhausted, the hard-worked man goes off for his autumn holiday, and, if he can, will spend most of it in the open air, either yachting, walking by the seashore, strolling in the country, shooting on the moors, or climbing the Welsh hills or the Swiss mountains. After a month spent in any of these ways, the brain-worker comes back to town feeling himself a different man. Instead of his work being a slavery to him, as it was before he started, he feels it to be a pleasure; he gets through it with ease, and feels not only that the amount he can accomplish is greatly