# Connecting the pavilion grounds and finding two different power plants

September 7, 2026. This pass connects more of the fair and corrects some early placeholders. The buildings remain first exterior studies.

## Roads between the national pavilions

Six connected road sections replace eight isolated fragments around France, Great Britain, China and their neighbors. Their centerlines follow the spaces between parcels on the [original ground plan](https://www.loc.gov/item/2007633932/). New paving is trimmed where it meets existing paving, so the same patch of ground is not drawn twice.

A closer look at the full-resolution scan caught a road north of France that was too far toward the agricultural grounds. We moved and narrowed it before publication. The large scan remains a research reference; visitors do not download it with the explorer.

There is still a real uncertainty in the central crossing: the map shows long planted strips, but does not clearly explain how the north–south passage crosses them. That junction remains schematic. Some older neighboring roads are also rough, and garden paths, surfaces and planting still need research. A connected model is useful, but it is not proof of an exact historical route.

## Two plants with similar names

The [general ground plan](https://www.loc.gov/item/2007633932/) calls the industrial building beside Machinery the Boiler House. Sheet 11 of the [Sanborn map set](https://data.library.wustl.edu/record/108214?ln=en) calls it the Power House. These are two names for the same mapped plant, already represented in our model. We corrected that building instead of adding a duplicate.

It now has a closer footprint and four plain cooling towers. Sanborn marks the main building and towers at 50 feet. It also marks iron chimneys 25 feet above the roof; those chimneys are still missing while we check their positions and shapes.

The separate campus Power House was in the wrong place. Comparing the general map with the [Pharus pictorial map](https://www.loc.gov/item/99466762/) puts it beyond the railway near the Jefferson and Service buildings, about 400 meters from our old marker. We moved it to that labeled footprint and adjusted the nearby railway to follow the map’s shallow curve. Its height and roof remain estimates. The road beside the industrial plant was also narrowed and retraced to stay clear of its walls.

## Liberal Arts takes its first plan shape

Sheet 14 of the [Sanborn map set](https://data.library.wustl.edu/record/108214?ln=en) supplies the Liberal Arts hall’s outline, four round corners and exterior recesses. It describes a solid hall with a roof full of skylights; those skylights do not establish an open courtyard.

We used its clear 70-foot height label for the first plain building shape. Other repeated 76- and 120-foot labels need further interpretation and do not yet control the model. The [Library of Congress photograph](https://www.loc.gov/item/2013649924/) shows how much architecture is still missing: a tall arched entrance, colonnades and elaborate roof details. The flat model is a footprint study, not a finished silhouette.

## What review caught

The Liberal Arts draft initially fitted the long side of one map to the short side of another. After that was corrected, a second visual reading caught a reversed setback along its broad frontage. Both errors could survive ordinary checks for collisions: a building can be easy to walk around and still have the wrong historical shape.

GPT-6 Astra handled the circulation, service-plant study, integration and independent review. GPT-5.6 Sol prepared the Liberal Arts source packet and first trace. Their work accelerated the comparison and implementation, but the corrections show why primary images, independent review and browser inspection remain part of the process.

We checked complete road widths, junction paving, building overlaps and the agreement between visible ground and walking height. Saved browser views cover the changed roads and buildings. These checks cover this bounded change; they do not certify every route across the fair.

The work continues with broad building coverage and better-connected grounds. Our overall completion estimate remains unchanged. More polygons alone would not justify raising it.