Figure 11 represents the best duck brooder I know of.
"Natural and Artificial Duck Culture"
James Rankin
This brooder is six and a half feet long by three feet wide, and will accommodate 150 ducklings.
"Natural and Artificial Duck Culture"
James Rankin
This tank is five feet long, twelve inches wide, and about an inch thick, and is hung about eight inches from ends and back of brooder, leaving nearly eighteen inches in front the entire length of brooder, in which to feed the first day or two.
"Natural and Artificial Duck Culture"
James Rankin