I should clarify that both Henrys and Spencers were used during the Civil War. Over the objections of the chief or military Ordnance. The Army did purchase 12,471 Spensers and 1,731 Henrys. Many more of the repeaters were bought by individual soldiers and units.
Both were very popular with troops. The Henry held 16 rounds of 44 rimfire. Confederate soldiers referred to it as "the damned Yankee rifle that you could load on Sunday and shoot all week". The Spenser shot a 56-56 rimfire round and carried 7 rounds in a tube in the butt stock.
Both were underpowered compared to the 45-70 and the numbers in service were a drop in the bucket compared to the number of Springfields used.