The letter reads as follows, with spelling and punctuation as per the letter.
To: Mr. Charles Stewart, Writer to the Signet, Edinburgh.
From: James Hog, Paisley Bank, Paisley.
Dated: 15th September 1791.
Sir,
I am favoured with yours of the 14th Currt. The Bill you mention lyes here under protest for non payt and amounts with charges including Int till tomorrows date to £201.6.3 as noted below which sum on you paying into Royal Bank on accot of this Compy and transmitting me this receipt the bill with protest will be returned to you in course ~ as we cannot give the Royal Bank any further trouble about it.
I am
Sir,
Your most obedient servant,
James Hog.
Bill McLeod & Stewarts acceptance for £200
Protest and 1/6 Com on Returned
Bills ½ per Cent £1 – Postage to &
From Edinr. 1/8 & Postage of your letter
here 4th Int till tomorrow 2/9 in all 1.6.3
£201.6.3
The letter is addressed to Charles Stewart, Writer of the Signet, Edinburgh. I have seen other letters addressed to this gentleman – some at 17 George Street, Edinburgh; some with the spelling as "Steuart" – with these spread over the period 1791 to 1821 and from landed Gentry. Other than to advise that Stewart must have been a prominent individual within the Scottish legal professional I regret I cannot add anything on the addressee.
James Hog was Cashier for the Paisley Banking Company and was engaged from the foundation of the Bank in 1783 through until c. 1799. He was the son of Walter Hog who was for many years the Manager in Edinburgh for the British Linen Company. Hog's duties included signing the Bank's notes and an example can bee seen under the Paisley Banking Company history section.

The content of the letter is routine and relates to a bill for £200 which is drawn on the firm of McLeod & Stewart and which remains unpaid. The Paisley Banking Company appears to have commenced the standard legal route for recovery of the funds insofar as they have had the bill Protested. The surname Stewart is very common in Scotland and I cannot therefore tell if Charles Stewart is a Partner within the firm of McLeod & Stewart; whether he has endorsed the Bill by way of an Acceptance (thereby becoming liable on the Bill) or whether he is acting as agent for the Drawer (McLeod & Stewart) in attempting to have matters settled. In any event the suggestion is that the Bill will be delivered to Charles Stewart upon payment of £201.6.3.
I am aware that the Paisley Banking Company did not have an agent in Edinburgh and it is therefore likely that Royal Bank of Scotland are mentioned here in the context of being the correspondent bank in Edinburgh.