Model 1870: http://jamesdjulia.com/item/1148-391/ Model 1872: http://jamesdjulia.com/item/1147-391/

Orvill Robinson was a gunsmith and gun designer in upstate New York who developed two rather interesting rifle designs in the 1870s. They are both pistol-caliber actions, with tubular magazines. The first (the 1870 model) used a tilting wedge very similar in concept to the 1886 Mannlicher straight-pull action. This Robinson design had a pair of checkered tabs on the back of the bolt, and the shooter would use them to manually cycle the bolt back and forth.

The later 1872 pattern rifle abandoned the earlier action for a toggle type of lock, operated manually with a small knob on the side of the bolt. The shooter would use it to pull the bolt open and push it closed. Much like a lever action, but without the lever.

Both guns seems to have had significant promise, which may explain why the Winchester company was interested in buying out Robinson in 1874. They purchased his inventory and patents, and Robinson signed a non-compete contract to boot. Winchester shut down the production; they were not interested in having a viable competitor to their lever-action rifles. Whether Ferdinand Mannlicher ever saw one of the 1870 pattern rifles is unknown, but it could have been the basis for his early 1886 action...

http://www.patreon.com/ForgottenWeapons