Page:Popular Science Monthly Volume 9.djvu/228

208 labor, and in the supply of a community with goods, has succeeded to an encouraging extent in Europe, and in some degree on this continent.

In domestic life, also, the burden of sustaining the usual isolated homes is beginning to be thought grievous and unnecessary. The constant repetition of the same details on a small scale, in cooking, warming, and attendance, is evidently subject to a large discount in cost, and increase of comfort, when a number of families combine to have a single kitchen, heating-furnace, and corps of servants. Many solutions of this problem have been attempted with various success; large houses rented in fiats, copied from European models, adorn some of the chief streets of New York and Boston, and hotels on all sorts of systems are to be found in our principal cities, numbering among their patrons thousands of families. It may be reasonably expected that in the near future some plan will be arrived at, and widely accepted, combining the benefits of individual homes with the advantages of association; but, for this result, an improvement in our present crudeness of social feelings must take place. Great is the premium placed on the growth of mutual harmony and confidence, yet how slow that growth is!

A process analogous to aggregation is that of concentration, which marks many of the forms of progress. When a force operates against a lesser one of constant amount, concentration multiplies its efficiency.

If a common furnace's heat is 3,500°, and a temperature of say 3,000° is required to melt iron, then but 500° of 3,500° are available for that purpose; but, when the same quantity of heat is presented at 4,200°, 1,200° of 4,200° may be utilized, an efficiency twice as great as the former. Hence the value of such an invention as the hot-blast, increasing the intensity of flame: the inert and diluting nitrogen is mingled with the oxygen of common air by the feeble force of diffusion; if they could be cheaply separated, it would mightily enhance the value of coal. Steam-engines, as now constructed, rarely yield in work more than a tenth the equivalent of heat applied; the chief waste is in the exhaust-steam, which, although in immense quantity, is of too low a temperature to raise more steam. Any feasible plan of concentration is all that is wanted to make the steam-engine more powerful; its duty has already been nearly doubled by the use of much higher pressures than Watt employed or sanctioned. A pebble on a sea-beach may have been exposed to the sun for ages without perceptible effect, but the focusing of a lens may reduce it to the liquid state in a few moments with no more solar beams than might have otherwise idly fallen upon it in an hour. This same principle also obtains in the operations of trade and business: the expenses of a railroad, steamship, or hotel, are pretty constant, and a certain amount of patronage pays them; beyond this point profits rapidly accumulate, and below it so do losses; small fluctuations produce large results in the balance-sheet.