Poor eyesight is admitted to be the cause of retardation in school. In many cases defective vision is the result of an abnormal condition of the mind, the mind is under strain, and when the mind is under strain the process of education cannot be conducted successfully. By putting on the glasses on the child we may make the child to see better but we are not able to relieve the strain which underlies the imperfect functioning. The result is that the power of glasses goes on increasing more or more.

