I'm roleplaying a "snuff" addict for my "Inventing the Constitution" class, and have been instructed to "pretend to partake in snuff liberally" throughout the Constitutional Convention. What did it look like? What would it be carried in? Was it tobacco or opium? How would a user use it, and how often? Thanks!
Additional note: the specific character is moderate Nationalist Oliver Ellsworth from Connecticut.
As others already explained, tobacco is finely ground tobacco, made from leaves that are mixed with brine, left to ferment, dried and finally ground until they resemble fine pepper or coarse flour. Depending on the snuff type, the powder may be left untreated or mixed with small amount of brine or diluted molasses to reduce the grain size.
Snuff is then inhaled through the nose. Judging from the contemporary descriptions, most common technique in 18th century was to pick a small pinch of snuff from the snuffbox with the index finder and thumb, put it to the nostril using thumb as a 'ledge' and sharply inhale. Later, in the early 19th century it was also common to put the pinch of tobacco in a small pit between the thumb and an index finger, raise it to the nostril and only then inhale. Snuff was commonly carried in portable snuffboxes, small enough to be carried in a pocket, but larger stationary snuffboxes capable of holding up to a pound of snuff were sometimes offered for guests' entertainment. In 19th-century Continental Europe it was also customary to offer the snuff to others before taking a pinch. Although taking snuff was usually followed by sneezing due to natural reaction, it was less common among habitual users, accustomed to the effects of the snuff.
After its introduction of tobacco, it was claimed to have many medicinal properties (most of them disproven by actual research), yet it was a common consensus that it is particularly good to ward off sleepiness* (nicotine indeed possesses mild stimulative and nootropic properties). Given that coffee was not really popular in late-18th century United States, drinking tea could have been politically charged after the 1773 and not everyone was fit for smoking (especially people with highly irritable air ducts), snuff could have been a stimulant of choice.
'I was in the camp when he [Gen. Dąbrowski] was recapturing Danzig from the Germans. He had something to write; and, fearing that he might go to sleep, he took a pinch, sneezed, and twice patted me on the back.'