Image #474 (4.5" x 2.75"): "6-21-29. Erecting the last bottom chord section L19' L21', north truss, east half of suspended span."; Image #475 (2.75" x 4.5"): "6-21-29. Connecting the closing bottom chord at L21'."; Image #476 (2.75" x 4.5"): "6-21-29. Closing B.C. joint L21'. Note 6" [diameter] pin and slotted hole with 7" movement for adjustment, temperature, etc."
