Attributions The files and metadata on this page have been mirrored with permission from The Telecom Archive. Bell System Practices (Pre-1960)DivisionH30DescriptionBuildings - Construction and Mechanical Plant Search Division: $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent $attachmentPatent
