David Nunes Carvalho

David Nunes Carvalho (September 29, 1848 - June 29, 1925) was an American ink and handwriting expert who provided testimony in notable legal cases and was the author of Forty Centuries of Ink, a book about ink analysis.

Early life and education

Carvalho was born in 1848, the son of noted artist Solomon Nunes Carvalho and Sarah Miriam Solis. He studied at New York College, where he specialized in organic chemistry and photography. He married Annie M. Abrams and they had six children. The family lived in Breezy Point in Far Rockaway, New York. In 1899 Carvalho sued The Jamaica Bay Turnpike Company to keep them from building a bridge connecting Rockaway Beach to Brooklyn claiming it would "completely destroy the character" of his property. In 1911 he bought a "country estate" in Roslyn, NY.

Career

Carvalho did early work with his father in his father's photography studio. He worked at a photography studio in New York City from 1877 through 1885. He worked with New Jersey Stereoscopic View Company likely in the 1870s and was working for the Bachrach Photo-Engraving Company in 1875. He filed for several patents for improving the photography process.

Patent 225458A a method to shorten exposure times by painting the studio an orange pea green color and coating the collodion negative with a film of violet colored collodion

Patent 234171A a method of producing photographic images

Patent 237246 a method for focusing frames using celluloid

Patent 237247 a method for photo backgrounds using celluloid

Patent 237248 a method for printing frames using celluloid