This is a nearly perfect example of an early spur trigger cartridge revolver from circa 1880. It's in caliber .38 rimfire with a five-shot cylinder and 3" octagonal barrel. From what little information we've turned up on this gun, it appears that "Aetna" was an early trade name used by Harrington and Richardson of Worcester, Mass. There was also an Aetna Arms Company based in New York that produced a copy of the S&W Model One Pocket Revolver but this company seems to be unrelated. Photos I've seen of early Harrington and Richardson (formerly known as Frank Wesson...Wesson & Harrington...and later Harrington & Richardson) spur trigger revolvers bear a remarkable similarity to the Aetna so this seems to fit. During the 1870's and 1880's, there were a number of manufacturers producing cheap pocket revolver with only nicknames or trade labels. Hopkins and Allen was one of the largest producers of these inexpensive spur trigger revolvers.
Overall Condition is NRA Antique Excellent with 99% original nickel plating on the barrel, cylinder, and grip straps. The frame retains 95% original nickel due to some flaking on the right side. Hammer still shows nearly all of its original case colors. Plain checkered hard rubber grips are Excellent with no chips, cracks, or repairs. Action works perfectly. Bore is in Fine Condition.