A glass manufacturing apparatus includes a forming apparatus defining a travel path extending in a travel direction. The forming apparatus conveys a ribbon of glass-forming material along the travel path in the travel direction. The glass manufacturing apparatus includes a cooling tube including a first end and a second end. The cooling tube includes a first tube including a closed first sidewall surrounding a first channel. The first tube receives a first cooling fluid within the first channel. The cooling tube includes a second tube including a closed second sidewall surrounding a second channel. The first tube is positioned within the second tube. The second tube receives a second cooling fluid within the second channel. The cooling tube includes a nozzle. The nozzle receives the first cooling fluid and directs the first cooling fluid toward the travel path. Methods include manufacturing a glass ribbon with the glass manufacturing apparatus.