[3] After the end of the war in 1848, Bell returned to Philadelphia, and joined the daguerreotype studio of his brother-in-law, John Keenan.

[1] In 1862, following the outbreak of the Civil War, Bell enlisted in the First Regiment, Pennsylvania Volunteers,[2] and saw action the battles of Antietam and Gettysburg.

[1] He spent much of 1865 making photographs of soldiers with various diseases, wounds, and amputations, many of which were published in the book, Medical and Surgical History of the War of the Rebellion.

[1] As part of the expedition, he captured numerous large format and stereographic landscapes of relatively unexplored areas of the Colorado River basin in Utah and Arizona.

[1] While traveling to Patagonia, where the Transit was observed, Bell took a series of photographs of the Rio de Janeiro Botanical Garden in Brazil.

[1] He was considered a pioneer of the dry plate and lantern slide processes, and experimented with night photography, using magnesium wire for lighting.

[2] He wrote technical articles on topics such as gelatine emulsions,[5] the use of pyrogallic acid to recover gold from waste solutions,[6] and the development of isochromatic plates.