Which statement is true about the 1870 Chicago signal update?

Which statement is true about the 1870 Chicago signal update?

• A. Call booths
• B. Clock boxes
• C. Call boxes
• D. Private booths

Answer: (A)

Urban signaling systems in the 19th century hinged on how smoothly operators could handle and relay alarms and requests. For Chicago in 1870, the update was to standardize and upgrade the dispatch environment by introducing call booths. These enclosed spaces gave operators a quieter, controlled area to manage incoming signals, place outgoing transmissions, and log activity, which helped reduce errors and speed up responses across the system. The other options point to different devices or concepts not central to this particular upgrade: street-level call boxes, timekeeping clock boxes, or private booths in a way that isn’t what this update describes.

Urban signaling systems in the 19th century hinged on how smoothly operators could handle and relay alarms and requests. For Chicago in 1870, the update was to standardize and upgrade the dispatch environment by introducing call booths. These enclosed spaces gave operators a quieter, controlled area to manage incoming signals, place outgoing transmissions, and log activity, which helped reduce errors and speed up responses across the system. The other options point to different devices or concepts not central to this particular upgrade: street-level call boxes, timekeeping clock boxes, or private booths in a way that isn’t what this update describes.