It's a normal English pair-case. In your picture #11, the cap over the movement can be removed by sliding the blue steel crescent-shaped piece clockwise, when it will just lift off to reveal the movement. There should be some hallmarks inside the back of the inner case if it's silver, and these should include a date letter.
Thanks for the pictures. As far as I can see, (the picture is rather blurred), the hallmarks show that it's sterling silver, it was assayed in London in 1874/5, and the case maker was William Carter at 7 President Street, Goswell Road, London. Note that Carter just made the case, (probably also the outer as well, although not necessarily, if it's also silver it should have a similar set of marks. Have a look under that leather patch). Watches were sold complete with the cases that had been made specifically for them.
The outer case is certainly quite solidly made, with heavier rims than usual, but I think it was unlikely to have been made for a specific environment such as mining. That wasn't the kind of place where any watch of the period would have lasted long, since cases weren't even dustproof, let alone waterproof or shockproof.
The movement signature is most probably for the retailer; I can't find an 'E.H. Farquarson' in Loomes, but there are several others with this surname, mostly in Scotland. Someone with access to postal and trade directories for the period may be able to expand on this.
Although only the balance and the fourth wheel are jewelled, the balance is a cut compensated type, so it's a better quality movement, at a time when many lower quality pieces still had plain balances. At this time, the city of Coventry in the Midlands was a major watchmaking centre and that's probably where this was made to Farquarson's order, complete with engraving.
Sorry, I didn't think to mention the fusee! Most English watches had fusees until the end of the 19th century. This has Harrison's maintaining power, (yes, that Harrison), which keeps the watch running when it's being wound, otherwise it would stop as the fusee is wound against the going direction. There's a thin steel ratchet wheel sandwiched between the fusee cone and the great wheel which drives the movement, and a spring in between the two is kept under tension as the watch runs; as the fusee is being wound the spring carries on supplying power to the train.
I think you're right about the signature being CH rather than EH. and there is a Charles Farquarson listed as working in Edinburgh in the 1860s, so he's probably your man.
The date letters in both cases are probably an 'i' for 1864/5 rather than a 't' for 1874/5, it's clearer in the outer case, (until 1975 the London letters were changed in May each year, so a given letter can apply to part of two years). The other marks are the leopard's head for London and the lion passant for sterling (0.925) silver.
Do you intend to dismantle the movement? If so there some points to be aware of.
To be clear, as Graham will confirm. The manufacture of the watch will have involved many hands, possibly over a number of years. Here is one possibly scenario.
The movement is likely based on a frame which start life in Lancashire. The majority of the work, to produce a working movement, was probably performed in Coventry where the signature of the retailer in Edinburgh was also added. At some point, possibly early in its construction, the movement would likely have been sent to London, to be fitted in a case made by William Carter. A number of individuals would again be involved - making a watch case also required specialist skills. The case was then sent to the London Assay Office and stamped with a date letter for the assay year May 1864 - May 1865. After assay, the case would have been received back by Carter to be polished and finished. It would have been returned to the 'wholesale maker' in Coventry who would have fitted the movement and done the final checks, prior to dispatch to Edinburgh, where it was retailed.
The date that the case assayed is the only date in the manufacture of a watch that can be fixed on the basis of the date letter for the specific office where the case was assayed. If the manufacture of the watch followed the standard procedure this enables its date of manufacture to be established reasonably accurately + or - a couple of years. It does not necessarily identify precisely the year when the frame was originally made, nor when it was initially sold.
I suspect your example, given it is housed in pair cases (higher price) but the movement would not have commanded the price of the advertised London Levers, would have cost between 6 & 8 guineas - mainly based upon 'B' quality Bennett prices.
Just for interest, a quick google threw up the fact that in 1865 the average wage for an agricultural labourer was about 11 shillings. A guinea is 21 shillings so on John's estimate we are talking about 12-15 weeks wages for an Agricultural labourer.
Today the national minimum wage in the UK is about £420/week - so the watch would have cost the equivalent of £5-6000 on a wage equivalent basis. About the same as a low end Rolex.