Mystery pistol - and a challenge

[ccdjg]

Here's one of my mystery air pistols that I have had sitting in a drawer for a few years and I thought I would give it an airing. Anyone know anything about it?
http://i135.photobucket.com/albums/q...ps532a5b44.jpg

Now here's a challenge. Can anyone work out from the photo how it cocks and shoots ? (Not you Trev – I know you have seen it before). All will eventually be revealed with some extra pix. It is a springer, and in all fairness I should tell you that I have left a cocking aid out of the picture to make it a bit harder.

The pistol is well made, obviously very old and almost certainly of British origin. It is inscribed with the "PAT. 1876", the initials B & C, and the number 4. I have never been able to locate a relevant patent from that year, but if anyone knows otherwise I would be delighted to hear from you. It shoots darts with a pretty hefty punch.

Let's see whose the sharpest of them all.

[I. J.]

Pure guess. Do you pull the piston/spring back with some kind of tool or key?

[magicesperanto]

Is it a pull out pop in?
As opposed to a push in pop out.

Or, if the barrel is fixed, then you poke a screwed rod into the back-end and pull the piston back to cock.

[ccdjg]

No, and no.

[magicesperanto]

Hmmmm......

Is the piston pumped back with air pressure by any chance?

[thisisdonald]

Is this a wind up?

[Rickyh]

Is the grip also the cocking arm

[GRAZY]

Does the trigger and lower frame slide along the cylinder then back to retract the piston?
It looks very interesting and in great shape for its age. Where did you find it?

[Tantomurata]

Cock it by pushing the piston back with a ramrod.