This is an OCR edition without illustrations or index. It may have numerous typos or missing text. However, purchasers can download a free scanned copy of the original rare book from GeneralBooksClub.com. You can also preview excerpts from the book there. Purchasers are also entitled to a free trial membership in the General Books Club where they can select from more than a million books without charge. Subjects: Photography / General; Science / Microscopes & Microscopy; Science / Optics; Science / Physics; Technology & Engineering / Electrical; Technology & Engineering / Fiber Optics; Technology & Engineering / Lasers & Photonics; Technology & Engineering / Optics;