Mode of preparing soluble Pyroxyline by the mixed Acids—by the Nitre process.—Purification of the Ether and Alcohol.—Preparation of the iodizing compounds in a state of purity 185

CHAPTER II.

FORMULÆ FOR SOLUTIONS REQUIRED FOR COLLODION PHOTOGRAPHS.

Section I.—Formulæ for direct Positive Solutions.—The Collodion.—The Nitrate Bath.—Developing fluids.—Fixing liquids.—Whitening solution 201

Section II.—Formula for Negative Solutions.—The Collodion.—The Nitrate Bath.—Developing fluid.—Fixing liquid 208

CHAPTER III.

MANIPULATIONS OF THE COLLODION PROCESS.

Section I.—Manipulations with moist Collodion.—Cleaning the Plates.—Coating with Collodion.—Exciting.—Exposing.—Developing. —Fixing 213

Section II.—Simple directions for the use of Photographic Lenses.—Portrait Lenses.—View Lenses.—Mode of finding the chemical Focus 227

Section III.—On copying Engravings, Etchings, Diagrams, etc.—Mode of intensifying the Collodion 231

Section IV.—Rules for taking Stereoscopic Photographs.—Mr. Latimer Clark's arrangement for working with a single Camera 232

Section V.—The Photographic delineation of Microscopic Objects.--Arrangement of the apparatus.—Mode of finding the chemical Focus.—Use of artificial light 235

CHAPTER IV.

THE DETAILS OF PHOTOGRAPHIC PRINTING.

Section I.—Positive Printing by the ordinary process.—Selection of the paper.—Preparation of Albuminized paper—of plain paper—of Ammonio-Nitrate Paper.—Preparation of the fixing and toning Bath.—Manipulatory details of Photographic Printing.—Mode of washing and mounting the Proofs 240

Section II.—Positive Printing by Development.—A process on Chloride and Citrate of Silver.—On Iodide of Silver.—On Bromide of Silver 259

Section III.—The Sel d'Or Process for toning Positives.—Preparation of the toning Bath.—Manipulatory details 267

Section IV.—On Printing enlarged Positives, Transparencies, etc., upon Collodion 272

CHAPTER V.

CLASSIFICATION OF CAUSES OF FAILURE IN THE COLLODION PROCESS.

Section I.—Imperfections in Negative and Positive Collodion Photographs.—Fogging.—Transparent and opaque spots.—Markings of all kinds—under- and over-exposure, etc. 276

Section II.—Imperfections in Paper Positives 285

CHAPTER VI.

LANDSCAPE PHOTOGRAPHY BY THE COLLODION PRESERVATIVE AND COLLODIO-ALBUMEN PROCESSES.

The Honey Keeping Process.—The Oxymel Process.—Photography on dry Collodion.—Taupenot's Collodio-Albumen Process 288