There seems to be some doubt who this is --Richard Drewry 1762-1850, or his son, Richardson Clark Drewry 1793-1855 .  It would be wonderful if it is Richard, but we need to to a little photography sluething. It could be either one - both lived during the days of the Daguerreotype photo process. J. Richard Drewry, who is in possession of the original, verifies that it is a Daguerrotype. 

The first photo in U.S. was in 1839 in New York. It was a Daguerreotype. These would have been popular in the 1840's and 50's. Mr. Brady, noted photographer of the Civil War, had Daguerreotype studios set up in New York in 1844 and was taking them even during the Civil War. The Calotype was introduced in 1841.  In 1857 the Ambrotype came into popularity, peaked in 1860, waned in 1862. The tintype period was from 1856 - 1930. The Carte-de-Vista came to U.S. in late summer, 1859, by end of 1860 was THE fashion throughout the country, peaked 1860-1866.

The Daguerreotype photo was on metal so using a magnet helps to classify it from an Ambrotype which was on glass.  The cases are not always a clue, as they were switched, left over ones from Daguerrotypes were used on Ambrotypes, no telling how long the photographer had his supply of Cases.

In early 1840's photograpy took off  in America, men learned how to to make them, set up studios in cities, traveled to cities and rented space to take photos.  The traveling "Saloon" [wagon] became popular, visiting towns and places where they could find people wanting to buy a photograph  of themselves.  Even some River Boats had photographic studios on major waterways, like the Mississippi River.

Richard was 83 in 1845 - abt. the  very earliest photos could have been in Weakley Co., TN -,  85 years old in 1847, 87 in 1849. 

Richardson Clark was 52 in 1845, 54 in 1847, 57 in 1850, 60 in 1853.  His dress might give us a clue but here again both men could be wearing this dress...also, I can't help thinking that men in rural Weakley probably didn't keep up with the fashions of the day, their suits might have been out of date. When we first moved to Memphis in 1973 it was a hoot, WE were 5 to 10 years ahead of fashion, hair styles, etc. - it was fun to be the trend setters!  There is the possibility that the photo was taken in Nashville on one of the Drewry trips. They would have made the trip after Richard's death to register his will. 

Some interesting links on photography with photos of the time......look them over, solve our Mystery.

http://lcweb2.loc.gov/ammem/daghtml
 

http://www.photo.net/history/timeline