PYROMETERS.

For Blast Furnaces, Bakers' Ovens, Boiler Flues, Superheated Steam Oil

Stills, Zinc and Lead Baths. E. BROWN, 311 Walnut st., Philadelphia.

* * * * *

_AGENTS WANTED._

To sell the UNIVERSAL SASH LOCK. IT IS SELF-ACTING AND BURGLAR-PROOF.

Send stamp for circulars. Carpenters and Builders can make from $10 to

$20 selling them. Address G. S. LACEY, care of Patterson Brothers, No.

27 Park Row, New York city.

* * * * *

SPERM OIL, _strictly pure_, for SEWING MACHINES and fine Machinery, in

bottles and bbls.

Sample by mail, 25 cts. W. F. NYE, New Bedford, Mass.

* * * * *

_THE REASONS WHY_

DOOLEY'S YEAST POWDER is preferred to any other Baking Powder in

market, are owing to its perfect purity, quality, quantity,

and economy. The ingredients are strictly free from deleterious

substances, and hence the full strength of each is obtained, and the

results are uniform every time it is used. This cannot be the case in

those of ordinary manufacture, and for proof of our assertion, we ask

those who have never used DOOLEY'S YEAST POWDER to give it a trial.

Your grocer keeps it. DOOLEY & BROTHER, Manufacturers, 69 New st., New

York.

* * * * *

PATENT CUTTERS for the Teeth of Gear Wheels, which can be sharpened by

grinding, without changing their form. Cutters made on this plan

will last many times as long as those of the common form, with the

advantage of being always ready for use. Descriptive circular, with

price list, sent per mail on application. BROWN & SHARPE M'F'G CO.,

Providence, R. I.

* * * * *

Scientific American, Volume XXIV., No. 12, March 18, 1871 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures. · 第 171 / 194 题