Clare Coleman
Hermann von Helmholtz showed that a square made of horizontal stripes appeared to be taller and narrower than an identical square of vertical stripes.
He used this information to note, in his 1867 Handbook of Physiological Optics, that “ladies” frocks with cross stripes on them make the figure look taller.
However, somewhere down the line his message got confused, and generations of women decided that horizontal stripes made them look fat. That was the received wisdom until last year, when Thompson decided to see who was right – the clothes-buying public or Von Helmholtz.
Thompson showed people pairs of drawings. Each set showed line drawings of identical women, one wearing horizontal stripes, the other wearing vertical ones. Participants were asked to judge which of the women was fatter.
The result? The figure in horizontal stripes was perceived as thinner than the one in vertical stripes. So Thompson drew the conclusion that horizontal ones make you look thinner, not fatter.
His theory was that when the eye looks at vertical stripes on a waistline, it has to take in the constant contrast of black to white to black, and so on, and all this extra thinking fools the brain into believing that the area is bigger than it actually is.
But when the stripes run from left to right, there’s a single unbroken line – so no confusion for the brain to sort out and no extra inches.
But all horizontal stripes are not created equal. It was found that