According to Horace Walpole, Dyson was the son of a tailor.
After having held a subordinate place in the clerical service of the House of Commons, in 1748 he bought the clerkship from Nicholas Hardinge for £6,000. ‘His tenure of the clerkship ... is mainly notable for his memorandum of 1751 which finally regulated the system by which fees on private bills were calculated, and for his contriving to obtain an official residence for the clerk of the House in the precincts of the palace of Westminster.’ On his retirement in 1762 he refused to sell the office, as had hitherto been the custom, ‘which example his successors felt bound to follow’.
In May 1762 Dyson became one of Bute’s secretaries to the Treasury, and in December was brought into Parliament by Administration. ‘His parts were excellent’, wrote Walpole.
mentioned Secretary Dyson’s being about to leave us on account of his health. That when he accepted the office from Lord Bute it was on condition that he might quit if he found the fatigue too great ... Mr. Grenville spoke of him with great praise; and mentioned in particular how exactly our minute books had been kept, as well as every other sort of business transacted. He certainly deserves this character, for never was a man of more integrity and knowledge or freer from vanity and official insolence.
Dyson held office continuously during his membership of the House of Commons, and was the great authority on procedure. Harris described him as ‘our great master of order’,
On the formation of the Rockingham Administration, Thomas Whately wrote to Grenville:
Dyson’s situation is said to be doubtful, but I understand that his sentiments are not so, and that whatever may be their determination he will not think himself much obliged to them: if he should stay, I shall be apt to attribute it to Lord Dartmouth’s wish to keep him, which he could not at first succeed in.
Dyson voted against Administration on the Anstruther election petition,
The conference lasted full two hours. It began with expressing great disappointment at the part I had acted, and proceeded to an enumeration in great detail of many of the causes of offence given through the whole session, descending even to such little circumstances of aggravation as had escaped my own observation. Before I entered upon any particulars I begged to know what was meant by the word disappointment. He readily acquitted me of any professions or other engagements than what must be understood to be implied by a man’s continuance in office. This I admitted as amounting to an obligation not to go into Opposition without notice, but that whatever was expected beyond that must depend upon the measures and the degree in which they were communicated. I then went through the particulars one by one. The business of the last day
The increased allowances to the King’s brothers. had been much misrepresented to him, and upon that article and that only I thought I made some little impression upon him, for ... it was easy for me to show him how much more offensively it might have been handled. He then told me that at the Board too I had always set myself to throw difficulties in the way of Government. This I own was quite unexpected, and I could not answer it without some warmth ... He left the subject of what was past, and said the situation of Government was become such that it was necessary for the King’s servants to know what they might expect or depend upon for the future ... I said that it was impossible for me to make any profession than that of acting up to my principles ... But whether the continuance in office or the removal of a man acting upon those principles would be most for his Majesty’s service belonged more properly to his Lordship’s consideration than to mine.
Rockingham wrote to the King that evening:
The difference of opinion which Mr. Dyson professes even in regard to the great commercial regulations and improvements which have been so much the object of the business this session, and will naturally both during the summer and at the meeting of Parliament occupy the attention and consideration of his Majesty’s servants, will certainly occasion great want of harmony; and, as Mr. Dyson’s conduct during great part of the session and even to the last day has rendered the cordiality of his intentions towards those now in your Majesty’s service very doubtful, Lord Rockingham can foresee nothing but disquiet and uneasiness in Mr. Dyson’s remaining at this time in his Majesty’s service.
The King consulted Northington, who advised him to dismiss Dyson only if he intended to continue the Administration;
According to Dyson, Chatham, on taking office in July 1766, had intended to remove him, but was dissuaded from doing so by Hillsborough.
Over the Wilkes case Grafton leaned heavily on Dyson. Shortly after Wilkes’s return for Middlesex, Dyson prepared a paper, ‘drawn up with great knowledge of the proceedings of the House of Commons’, wrote the King,
I take the parliamentary law to be this: that no man who has been expelled shall sit again in that Parliament ... It has been supposed that the county of Middlesex will continue to return Mr. Wilkes ... If that county shall think proper to vote for Mr. Wilkes and another is returned by twenty freeholders only, the rest will have given their votes unnecessarily.
‘I should have been justly blameable’, wrote Grafton subsequently,
Dyson lost a good deal of consequence when North, a commoner, became head of the Treasury. In October 1771 he was reported ‘extremely ill’,
He died 16 Sept. 1776, aged 54.
