Between EEI to ConEd
The original Edison Electric Illuminating Co of New York was merged with several other power companies in 1901 to form New York Edison, all under the umbrella of the Consolidated Gas Co. (its complicated). New York Edison during those decades mostly used the cojoined CT & ES Co Ltd. for building and maintaining its underground conduits in Manhattan and the Bronx. But there are several examples with this striking design, a design that eventually became emblematic of the company when it later merged with 6 other electric and service companies across New York City to form Consolidated Edison in 1936.
DESIGN:
The design can be linked to earlier NYE and EEI designs that were basically wheel and spokes with 24 coffered spaces in the outer rings. The addition of raised circular stubs, each with a drilled vent hole, produced a striking design that is still being used today (although not by Con Edison!)
UTILITY:
The manhole covers with vents were needed because generally high voltage AC current coming from central generators was converted into lower voltage DC current, ready to be sent to consumers, from these points. Much heat was generated in the process.
RANGE:
There are a few scattered EDISON covers around Manhattan, this one is on First Ave between 39th and 40th Sts. Many more identical covers were produced by the Brooklyn Edison Company at around the same time, and can often be spotted in that borough.