Rainbow sails were BIG

Rainbows sails were 7500 square feet.  They were made of real heavy duty canvass not the light synthetic materials of today that are light and shed moisture.   (Ever handle wet canvass? Heavy isn't it!)

They would cover a building lot 75 feet wide by 100 feet deep

(larger than building lots in many developments)

They would cover almost all the infield of a regulation size baseball field

And they had to be brought up from below decks, through a hatchway, and raised and then  lowered, dried, folded and stored below decks after each use ALL BY HAND-POWER