On this day (November 2) in the year 1839, the following news item appeared in "The New-Yorker" (Vol VIII; No. 7; page 100; col 3): ----------------------------------------------------------------- THE DAGUERROTYPE.--The first exhibition of this machine in London took place Sept. 13. M. De St. Croix, a French gentleman, performed the operation with great dexterity and complete success. The house in which he exhibited the performance is situate close to the Regent Circus, Piccadilly, and having a view of part of Regent street and the Circus. This view he proposed to represent to the spectators. He first took a sheet of copper, plated with silver, which he washed carefully in a solution of nitric acid, which removes from it all the extraneous matters on its surface. A slight degree of friction is requisite in this process, but it must not be applied always in the same direction. When the sheet is thus prepared, it is placed in a closed box and exposed to the vapor of iodine for fully ten minutes, the room being kept quite dark. A thin coating, of a yellow color, is thus formed on the surface of the sheet. The sheet, when covered with this substance, is of the most excessive sensibility to light, and is thus ready for the camera obscura. M. De St. Croix ascertained the exact point at which the sheet should be placed, and having done that by means of a mirror from which the objects were reflected, he placed the sheet in the camera obscura, where it remained for fifteen minutes. When taken out it was quite dark--not indeed a vestige of the street or houses could be distinguished till it was exposed to the vapor of mercury heated to about 180 or 200 degrees of Fahrenheit. He then washed it with a solution of the hyposulphate of soda, the solution attacking the parts upon which the light could not act, and respecting the light parts, being the reverse of the action of the mercury. He next washed the sheet with distilled water, and the image, though the day was rather cloudy, exhibited the most perfect likeness of the houses, the street, and the blue sky. The operation altogether occupied nearly an hour, but it can be performed in much less time. ----------------------------------------------------------------- 11-02-95