We have had this discussion before regarding the origins of these clocks.
There is no one "test" that determines origin. In many cases it's the accumulated evidence that only points to a possibility.
How definitive is that.................?
Some observations on this clock. Nice rafter "straight line plates" , a thin squared tall look lends itself well to the use of a square dome.
Back in the 1870's and for some time after these were "a hot item". At that time they were made by legitimate clock companies and also "assembled" by retailers and small clock houses.
This particular clock has some features that indicate standard parts were used to put together a nice looking clock without making specific parts other than the frame. Even then frames could be purchased if needed. By using readily available parts this lowered manufacturing costs but meant having to follow constrictions based on the parts available.
Check out the minute wheel, no cock. Not a very common practice at that time for English construction. It is mounted to a post because A, it's simple and B the plate geometry and design does not
lend itself to the addition of a conventional cock. It would look ugly even assuming there were the meat on the plates to add such.
Second. The dial is simply a conventional parts Chapter ring with internal scollops. Nothing on the outer edge as there would be no material to work with. In other words they did not make a dial to suit the clock form but again used "standard" parts and "dressed them up".
Third as others have already observed the mount for the pendulum (not easily seen) is a simple post, not a bridge and does not allow for removal of the verge as it is now fixed between the plates. Also the pendulum drop is not correct in proportion to the plates. The mount had to be raised to achieve the drop. Not too hard to design plates for a known drop but if you are "using what's available" you do what you have to do. Again the design does not lend itself to the use of a bridge but even on these types of plates some makers at least attempted some version of a bridge when manufacturing a clock "from scratch".
Five spokes........... More sought after than four but not a determiner of origin on its own.
The label in the base..............don't be fooled but such.
Let's say you have a movement made by these guys. You take the wheels and make your own frame, a little sawing, a little drilling and you have a clock.
So, how difficult would it be using those same skills to saw out the makers name off the plate and insert it into the base ? It's not, and such "deception" is done.
So where are we ? This isn't likely a clock made by someone set up to "manufacture skeleton clocks". This is a clock made from conventional readily available parts and worked into the form of a Skeleton clock. Maybe by a parts house, small workshop or other and it could have been made well over 100 years ago. Condliff made some very much sought after clocks this way so it's not necessarily a negative feature, simply a practice of the time.
If this is truly a clock by this company it is very likely it's not the only one they made. It is equally likely they followed the same practice of seating their tag in the base. There should be others out there and finding one would very much seal the deal suggesting this is a small clock house fabrication from standard parts. Without such confirmation it's speculation as to the origin and that is not unusual for these clocks. Sometimes it's part of the mystery................
It's a nice clock to enjoy, has good lines and a nice look to it.
Addition......
Just as a quick addition to bring together Les's and Laprade's observation re wheel crossings.
Even established manufacturers used solid wheels occasionally on the cannon pinion and minute wheel.
One real "deal killer" for me is when I see a solid hour wheel. These do appear from time to time but score high on my "fake" meter. This is a very common sign of being a dial clock conversion. If you think about it the very essence of "Skeleton clock" is "opened up" and there staring you in the face is a big solid hour wheel. Uuuuuuugleee..............
Wheel crossing is definitely something that adds appeal to these clocks and factors into price and appreciation. The "crossing count" or number is not "generally" something that should factor into considerations of "originality".
JMO