Feargus O'Connor's letter: deciphering a Chartist mystery

I recently came across and could not resist buying handwritten letter by the Chartist leader Feargus O’Connor dated 20 October 1838. The letter is badly water stained and carries a rusty mark from the paperclip which must have attached it to other papers for quite some time.

Despite the damage, most of the letter is legible. But O’Connor’s handwriting is far from easy to make out. I can only pity the poor typesetter who had to decipher the many thousands of handwritten words that made up O’Connor’s weekly contributions to the Northern Star.

I have no illusions that the letter is of any great historical significance, although I do wonder whether the O’Brien referred to is James Bronterre O’Brien, the Irish Chartist and journalist who wrote for the Star while also publishing his own journals.

What I can read with some confidence is set out below. If you have better luck than me with the missing words and phrases, please do let me know.

Denham Cottage
Oct 20 1838
Sir
In compliance with your xxxxx I send a bill for 30£ in favour of Mr O’Brien which is intended to be drawn by you and accepted by me xxxxx that without reference to any subsisting agreement between you & Mr O’Brien I shall make provision & take up the Bill myself.
I am your xxxxx
Feargus O’Connor

Update: I am grateful to The Everyday Archivist (Twitter handle @TEA_archivist) who got in touch shortly after I posted this to fill in the gaps.

The full inscription now reads:

Denham Cottage
Oct 20 1838
Sir
In compliance with your propo =sal I send a bill for 30£ in favour of Mr O’Brien which is intended to be drawn by you and accepted by me and I beg to say that without reference to any subsisting agreement between you & Mr O’Brien I shall make provision & take up the Bill myself.
I am your obedient servant
Feargus O’Connor

Many thanks for sharing your knowledge and archival experience.