Carbon print
Discovered in 1855 by A.L. Poitevin, the carbon process was the first to produce photographic prints that were permanent as they contained no silver impurities that would deteriorate over time. Paper coated with a gelatin containing a carbon black pigment was exposed under a negative in daylight. The paper was then washed to remove the soluble gelatin leaving the residue carbon image. The process was popular between 1870-1900 and produced either black or deep rich brown glossy dark prints.
John Hanning Speke
by Southwell Brothers
1863
NPG P658
Queen Alexandra
by Symonds & Co
1877
NPG x17460
Queen Victoria
by Alexander Bassano
1887 (1882)
NPG x38284
Sir Sayaji Rao III, Maharaja of Baroda
by Unknown photographer
published 1889
NPG Ax28670
Mary Augusta Ward (née Arnold)
by Herbert Rose Barraud, published by Eglington & Co
published 1889
NPG Ax5470
Sheikh Chidda; Queen Victoria
by Hills & Saunders
17 July 1893
NPG P51
Lord Henry Cavendish-Bentinck
by J. Rogers
1900s
NPG x144175
Cecil Henry Meares; Lawrence Oates
by Herbert George Ponting
26 May 1911
NPG P121
Robert Falcon Scott
by Herbert George Ponting
7 October 1911
NPG P23
Albert Ball
by Argent Archer
circa 1915
NPG P657
Lallie Charles Cowell (née Martin)
by Rita Martin
circa 1920
NPG x125438
Hester Sassoon (née Gatty)
by F.J. Arnott
mid 1920s
NPG x45991