-saving Tools. p. 333.

* * * * *

PATENTS ISSUED TO AMERICANS.

FROM NOVEMBER 9 TO NOVEMBER 12, 1880, INCLUSIVE.

Book binding, L. Finger, Boston, Mass.
Draining and sewerage. G. E. Waring Newport, R. I.
Electric gas lighter, G. D. Bancroft. Boston, Mass.
Electric signal. EH Johnson _et al._, Menlo Park, N. J.
Horse nail manufacture, S. S. Putnam. Boston, Mass.
Hygienic confection, T. S. Lambert _et al._, New York city.
Looms, F. O. Tucker, Hartford, Conn
Reflectors for lamps. J. S. Goldsmith, New York city.
Railroad vehicles, E. R. Esmond _et al._. New York city.
Sewing machine. G. F. Newell, Greenfield. Mass.
Steam boilers, D. Sutton. Cincinnati. Ohio.
Steam boilers, W. D. Dickey, New York city.
Toy money box, J. E. Walter. New York city.
Trucks, hand., E. J. Lyburn, Fredericksburg, U. S. A.

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* * * * *

(1) L. L. asks: 1. How can I grind and polish quartz and agate rock,
and what kind of grinding and polishing material should I use? A.
Quartz and agate are slit with a thin iron disk supplied with
diamond dust moistened with brick oil. The rough grinding is done on
a lead wheel supplied with coarse emery and water. The smoothing is
done with a lead lap and fine emery, and the polishing may be
accomplished by means of a lead lap, whose surface is hacked and
supplied with rottenstone and wate