The Placement of Overlays and Buildings

The main challenge in placing an overlay of a sketch, or map, from the Plan was to find points common to the sketch and the satellite image of modern Chicago. Placing them by sight depending solely on the transparency feature of the overlay and the resize features proved impossible.

At first, the Chicago River and lakefront area, including Buckingham Fountain were used as the main guides in placing an overlay. This approach led to various complications and issues, since the Building of Natural Sciences was supposed to be further west according to the Plan. Moreover, the path of the Chicago River was straightened after the Plan was conceived. Hence, the river from the Plan did not match up on all points with the river in Google Earth.

As a result, streets were chosen as points for the matching process. Streets in the idealized sketch do not match up perfectly with the actual streets of modern Chicago—because the sketch did not originally match reality and/or Chicago’s streets were changed over time. Nonetheless, the streets were determined to be the best source for matching because they were likely to have changed less than the lakefront and the Chicago River. Various sources were used to determine the common streets and avenues in place at the time of the Plan and still existing today. Sketches from the Plan indicate that Michigan Avenue, Congress Parkway, Roosevelt Road, Halsted Street, Canal Street, and Blue Island Avenue were present at the time the Plan was written.  With these streets as starting points, the overlay image was resized and moved to match these points. The “roads” layer in Google Earth was turned on to show the highways/roads and the transparency of the image was also controlled as required for better viewing during placement.

The Placement of the CXXIX Overlay along with Buildings in Grant Park

The CXXIX overlay is a map sketch of Monroe Harbor stretching across Grant Park and to the Civic Center near Halsted Street and Congress Parkway. Michigan Avenue, Congress Parkway and Roosevelt Road were the first points that were matched. Washington Boulevard and Randolph Street were also considered as guides, since they intersect the northern side of Grant Park, but they would not match up even after increasing the proportions of the overlay.  An additional problem with increasing the proportions was that the Building of Natural Sciences, along with some streets, drastically shifted out of place.  Halsted Street, Canal Street, and Blue Island Avenue were used as additional guides to anchor the sketch to modern Chicago. The overlay was then used as a blueprint for placing the Grant Park buildings onto Google Earth. A balance was struck between trying to match the buildings’ placement in the idealized sketch with their placement, using the streets as guides, in modern Chicago, as not all streets intersecting Grant Park today are located exactly as they are in the sketch.

The Placement of the LXXXIX Overlay

The LXXXIX overlay is a map sketch of Chicagoland indicating street circulation and parklands in relation to population.  Even though this map covered more territory than that of the CXXIX map, the same technique was used to place the overlay with the same six streets as guides. With this overlay, however, unconstrained resizing, which does not preserve the ratio of an image’s width and height, was used to match the harbor area better once the guide streets aligned.