That’s a fantastic picture on the cover of Scientific American, showing a proposed two-level subway below Broadway. In 1905, the first subway, the IRT, had just opened, and the stretch of Broadway shown did not yet have service.
The combination of a section through the street sub-grade and a perspective of the buildings and street above is quite effective in illustrating the point being made: constructing a four-track line interferes less with the existing buildings if it’s double-decked, as the excavation (all early NYC subways were built cut-and-cover) would be kept away from the buildings. The pipe galleries on either side of the subway, providing easy access to utilities, unfortunately were never built.
The illustration shows a view that could never exist in reality, and does so using a reasonably common technique of the time: a combination of hand-drawn art on top and supplementing a photograph. Here’s a similar shot of 584 Broadway – the big loft building on the right, from a few years later: