The original treatise, which this volume succeeds, was first published in 1897 under the title Optician's Manual". It had the distinction of being the first authoritative work published in the United Stated devoted solely to the science of eve-refraction and the art of sight-testing and spectacle litting.<br><br>The practical value of the work has been well attested by the enormous demand for it, requiring new editions in rapid succession..<br><br>In the present edition the title has been changed to "Optometrist's Manual" as better expressing the character and scope of the subject matter of the work, a change, by the way, which should have been made long ago, for the practitioners of drugless eye-testing and eye-glass fitting have tor some years been known as optometrists.<br><br>But tradition and sentiment bind one to a hook title as they do to a name. Both author and publisher have therefore, been loath to change a title that has meant so much to a large majority of those who practice optometry and who obtained the groundwork of their optical and ocular knowledge from this and its companion Volume II<br><br>A concurrent edition of the second volume has been printed under the new title, both being revised before reprinting.<br><br>"Optometrist's Guide" Volume I and II form the mo-t comprehensive single treatise on the essentials of optometric science and practice available to student and practitioner.<br><br>Under its new title this work, we hope, will continue to find an ever-widening circle of -students and friends as its predecessor under the original name.