Issue 11 and Volume 26.

A NEW MANHOLE COVER. The demand for a good manhole is apparent. They must be constructed so as to present no obstacle to traffic and no danger to life or annoyance to the nerves of man or beast who have to travel over their surface. The Greger noiseless manhole cover over-comes nearly, if not all of the faults found in the covers of the old type. Compared with them it bears the same relation as the tallow candle does to an electric light or horse propulsion to electricity. The Greger cover consists of astrongnietal circular frame filled in with an asplnvltum composition peculiar to the purpose. The tilling is, and maintains itself flush with the rim of the cover, which is sunk into a frame set into the pavement flush. The depth, fit, and support of the sink are such, that the coverisimmovable by the pressure from above, and the…

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