AN INGENIOUS VENT PEG.
The engraving illustrates an English invention of value in that it provides a means of giving vent to casks from which liquids are to be drawn, at the same time excluding the air when the drawing is discontinued, and thus preventing deterioration in the liquid by undue exposure to air.
The principle on which it operates is that of admitting just so much air as may be required to fill the vacant space produced by the withdrawal of the liquor from time to time, and affording this air no egress, thus hermetically sealing the barrel. This is effected by means of a valve opening inward, at the upper portion of the peg, so long as the density of the exterior air is in excess of that within. This action takes place at the very instant of the flow of the liquid, and ceases with it; for at that instant all further supply is shut off, there being no further pressure.
THE LARGE TREES OF TEXAS.--The large court-house of Navarro county is said to have been covered with shingles made from a single cedar tree. The oaks, pecans, and cedars of that section of the country attain an immense size. A pecan tree in Navarro county, on the banks of the Trinity, measured twenty-three feet in circumference. The cedars are often more than 100 feet high.
ELECTRIC MESSAGES.--Although it may require an hour, or two or three hours, to transmit a telegraphic message to a distant city, yet it is the mechanical adjustment by the sender and receiver which really absorbs this time; the actual transit is practically instantaneous, and so it would be from here to China, so far as the current itself is concerned.