It is a style of pocket knife referred to as a friction folder. This style of knife can be traced back to at least Roman times, but the one you have here was likely produced in, or around, Trattenbach Austria where they have been in continuous production since at least the early 18th century. Other versions of these knives were produced in Spain, Poland, and no doubt other countries as well. Bernard Levine, a noted knife expert, once stated that he felt the term "Penny Knife" was a modern one, but I have found 18th century references to Penny Knives, the problem is that the references seem to be often describing any relatively inexpensive knife and not necessarily a simple friction folder like the one you have acquired. I have seen a number of knives of this style, and as I mentioned earlier I have no doubt they were readily available in during the 18th century, but finding ones that can be definitively dated to that period is difficult. Partly this is I feel because the basic style did not change much over time and one produced at the end of the 19th century probably did not look much different than ones produced in the 18th. Also, because they are very basic knives with few metal parts their survival rates would have been very low.
Gene Chapman wrote a short manual on building these knives and it is a good place to start if you want to build one. I have built a number of them and though I do things a bit differently the basic concepts are the same. I have included some images of knives that I have built and also some in process. They are a fun knife to make and despite their simplicity are very effective and easy to carry due to their light weight. The Opinel is a more modern version of this knife and still highly popular today.
The next three images are a knife I built awhile back. This is based on examples that were likely produced in Poland in the 19th century, though I don't have much difficulty believing that 18th century versions were about the same.
This one is similar to the one that you have here and seems to be the ones that most often are associated with "Penny Knives". This style is common in Austria, produced in Trattenbach. The one here has a Rosewood handle, though beech and maple would probably have been more common materials.
A couple pictures of a similar knife with a cherry handle during test fitting, but before final assembly and finishing.
A similar knife being turned in the lathe. I have a wood lathe, but like to do most of my turning on a small 7x12 metal lathe.
A photo of the slotting fixture that I made to create the recess for the blade.
A slightly different style handle, based on one I found in a Polish collection. I have not got around to finishing this one yet, but at some point I will get it done. I generally do finish the handles before I mount the ferrule and attach the blade.
