Light (Rural Electrification Administration poster)
The pattern
This still is filed under Image carries the claim.
Define
One image does the entire argument. Copy, if any, is a caption, not a second ad.
Mechanism
Pictorial claim. The picture is readable as a sentence. If we need a paragraph, we picked the wrong picture.
Verdict
The idea is visual and the surface is a poster, a feed, or a silent frame.
Why it works
The entire argument is drawn rather than written: bulb, rays, lit windows. Beall gives the bulb monumental scale and then puts the benefit word inside the object that delivers it, so the word and the thing cannot be recalled separately. Flat colour fields with no modelling, no gradient and no landscape detail keep the poster readable at distance and printable in three inks on cheap stock. The rays are the only diagonals on an otherwise strictly horizontal sheet, so the eye is dragged from bulb to farmhouse on every pass - which is precisely the cause-and-effect claim the agency needed to make.
Steal this when
Use this when a single benefit has to land at distance on a distracted or low-literacy audience: set the benefit word inside the object that produces it, and use the only diagonal on the page to draw the line of cause.