A Manual Of Photography

320 INDEX. Precipitates on glass plates, 100. Pressure frames, 197. Priestley, Dr., on influence of light on plants, 6. Prinsep, Macaire, on change of colour in leaves, 6. Printing, photographic, 29. -------process, 223. Prismatic spectrum, 116. Processes, modified, 224. Production of positive photographs, 292. Proto-nitrate of iron in collodion pro- cess, 267. Proto-sulphate of iron in collodion process, 267. Prussian blue formed by sun’s rays, 52. Radiations, solar, distinguishing cha- racter of, 135. Rays, exciting and continuating, 146. -------, heating of, spectrum, 118. -------, oblique, 179. -------, parallel, 178. Ritter discovers chemical action of dark rays, 5. Reflecting camera, 107. Refraction of coloured rays, 181. of light, 177. Registration, photographic, 153. Remarks, general, on camera obscura, 299. Redman’s solution, 243. Researches on the chemical action of the solar rays, 3. Rest for head of sitter, 302. Rosse, Lord, on photographic patent right, 312. Ross and Thompson, their photo- graphs, 283. Rumford, Count, on the chemical pro- perties which have been attributed to light, 4. Sage, M. B. Gl., on realgar, 9. Sandford, Mr., specimens of paper, 189. Saussure, action of light on plants, 7. Schafhaeutl, Dr., on hydriodic photo- graphs, 297. -------, his negative process, 97. -------process on carbonised plates, 98. Scheele examines the action of the spectrum on salts of silver, 4. -------on the reduction of luna cor- nua, 126. Scientific investigations, Part II., 113. Seasons, photographic variations of, 122. Seebeck on chemical spectrum, 5. Seguier, M., modifies daguerreotype, 249. Senebier examines the darkening of chloride of silver, 4. Senecio splendens, photographic ef- fects, 71. Sensitive paper for engravings, &c. 209. papers, to prepare, 205. preparations, 124. surface of daguerreotype plate, 137, 242. Shaw, Mr. Gk, experiments on da- guerreotype, 139. Silver, bromide of, 132. , ferro-tartrate of, 61. , fluoride of, 84. , fulminate of, 134. , iodide of, 209, 130. , nitrate of, 125. , chloride of, 125. , phosphate of, 132. salts, various, employed, 133. , tartrate of, 134. Silvering composition, 254. copper-plate, 254. Simplification of the daguerreotype, 254. Sizes employed in paper, 189. Soda, hyposulphite of, a fixing agent, 213. Soda and potash hydriodates, 290. Solar agency producing chemical ' change, 115. -------rays, researches on the chemi- cal action of, 3. Somerville, Mrs., on magnetism in- duced by violet rays, 5. Sparaxis tricolor, action of light on juice of, 70. Spectrum impressed on hydriodic pa- pers, 297. -------, prismatic, 116. Spherical aberration, 180. Stands for camera obscura, 204. Stand, levelling, for plates, 253. Statues, to copy, 299.