Martin Carriage Works Correspondence

Following are envelopes from the Martin Carriage Works.  Note the carriages being shot out of a canon!  This must be an early letter envelope because it only has a 1 cent stamp.  The cancellation date is not legible.  This is the only envelope that I have see with a one cent stamp, most have a 2 cent stamp.  Also, I find it interesting that letters arrived successfully with just a name, city and state.

Another Martin Carriage Works envelope. Probably a later date since it has a 2 cent stamp.