AbstractGelatin solutions shrink as water evaporates from the gel. If the shrinkage is prevented, tensile stresses develop. A technique is described for measuring the tensile stress developing in the plane of edge‐clamped gelatin films during drying. It is based on measurement of the elastic deformation of the film when stressed normally to the plane of the film. A stress of 4000 pounds per square inch was observed in a dried gelatin film. The reality of the stress was confirmed in a completely independent manne