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The two other points tolerate stress but only as the result of the weight bearing point.
Its weaknesses become clear if stress is applied at the other points of the triangulation.
However if struts are placed in anticipation of vulnerable attacks, such difficulties may be overcome.
The weakness therefore – lie between the three points and in particular between the two stress-supports resting on the base.
A few graphic studies of applying pressure on or between points of a triangle demonstrate unreliable geometric results.