bolted to the wall so as to bring the brackets to the proper height for handling the lids. The luting bench, situated near the

brackets, has shelves under it, on which are placed the prepared lids ready for use. The two pairs of brackets and bench as shown are ample to take care of the lids for five benches of 6's."

By Pass for Hydraulic Main Seal.-The arrangement shown in Fig. 2 is offered by Mr. Frederick Egner. He writes as follows:

"Originally it was introduced somewhere in 1870 or 1871, at the works of the then Metropolitan Gas Light Company, of New York City, and some years afterward was patented by somebody who reinvented the device; but the original designer did not apply for a patent, and even the first patent has long ago run out. The object of the device is to by-pass the seal in the hydraulic main to some extent, the result being less carbon deposits in the retorts, reducing thereby the time lost through scurfing. That is one result. Another is, if the device is properly manipulated, an increase in quantity of gas recovered, as well as a slight increase of illuminating power. But this last can be reversed

very easily, if the by-passes are not closed at the time the retorts are open, or if it is otherwise neglected, or if the superintendent wants to increase his yield merely by means of the exhauster. I have used these by-passes in sizes from 12 to 2 inches in diameter, and always with satisfactory results; especially when applied to the ascension pipe of a retort in which oil was being carbonized for enriching purposes."

Tar Overflow for Hydraulic Main.-Two forms of appliances are shown. One (Fig. 3) is sent by Mr. V. L. Elbert, and is described as follows:

"It is especially applicable in gas works situated in cold climates, where sealpot for overflow usually freezes up, or gets coal dust or other substances mixed in it, requiring the frequent cleaning of the overflow pot. The seal can be altered by the lowering or raising

Tar Pot

Overflow

of the pipe A, and the pipe A is very easily cleaned, as you will see. I have used them at several gas works with greatest satisfaction."

Mr. W. H. Odiorne, of Springfield, Ill., contributes the tar offtake, as shown in Fig. 4. It consists of a length of 12-inch cast iron pipe, placed on floor perpendicularly in front of end of hydraulic main. The pipe is closed at bottom, and is connected with