Eye defects: how to detect and correct them

Historical Significance: Knowles held an MD degree and is author of other books including "Practical optics" and the "The science and art of refraction". The book is published by an optical manufacturing company as promotion and to educate its clientele of opticians, optometrists and ophthamic medical practitioners. This book is undated but from its style and content it would have been published about 1910 to 1920. Some of the pages advertise ophthalmic equipment and on page 95 is an advertisement for the Spencer Optical Institute which provided a two week course costing $US25 starting on the first Tuesday of each month from which a Diploma could be obtained. The illustrations of equipment and spectacles are excellent and the photographs of optometrists doing various procedures provide a very good picture of the practice of optometry at the time. Second copy Kett No.108