Complex sentence: By 1913,54 Hulett machines were in service; two were built at Lake Superior (unloading coal) and five at Gary, Indiana, but the vast majority were along the shores of Lake Erie.
Split into simpler sentences: By 1913,54 Hulett machines were in service. Two were built at Lake Superior (unloading coal) and five at Gary, Indiana, but the vast majority were along the shores of Lake Erie.