[128] See page 360, vol. xvii. of the former series of this Journal.
2. Improvement in Steam-engines.
| April | 61,877,545 |
| May | 60,632,179 |
| June | 61,762,210 |
| July | 62,220,820 |
| August | 61,764,166 |
thus exceeding by nearly fifty per cent. what had been effected before that time.
3. Improved Clock.
4. Method of dividing Glass by Friction.
“By means of the fork, the glass is easily held steadily by the hand of one operator; by means of the kerf, the string, while [p455] circulating about the glass, is confined to the part where the separation is desired. As soon as the cord smokes, the glass is plunged in water, or if too large to be easily immersed, the water must be thrown upon it; the latter method is always preferable when, upon immersing the body, the water can reach the inner surface. As plunging is the most effectual method of employing the water in the case of a tube, I usually close the end which is to be immersed.”—Silliman’s Journal, xiii. 7.
5. Use of Soapstone in diminishing Friction.
Some idea of the value of soapstone thus applied, may be formed from the following fact communicated by D. Moody, Esq., the superintendent of the tar-works on the mill-dam near this city. Connected with the rolling machine of that establishment, there is a horizontal balance-wheel, weighing fourteen tons, which runs on a step of five inches diameter, and makes from seventy-five to one hundred revolutions in a minute. About one hundred tons of iron are rolled in this machine in a month; yet the wheel has sometimes been used from three to five weeks without inconvenience, before the soapstone has been renewed. The superintendent thinks, however, that it ought to be more frequently employed.
“The use of soapstone was discovered at Lowell. It has been said never to fail in producing the desired result when applied to machinery which had began to be heated, even in those cases when nothing else could be found that would answer the purpose.”—Silliman’s Journal, xiii. 192.