Did Sir Arthur Conan Doyle coin the proverb "A change is as good as a rest"?
The poem found by Andrew Leach as the earliest use in the OED, "A Change Is As Good As A Rest", is printed on page 270 of The Family Herald, Volume 15, 1857, published in London by George Biggs. Google Books finds it here, although the snippet view there is now so unreadable as to be useless. There is a note on the Family Herald here. I cannot find the date of that publication.
It was published in the Hampshire Advertiser in England on 29 August 1857. Registering an account at the British Newspaper Archive allows access to three free pages. Their terms permit noncommercial reuse, so I used one access for this and found:
A Change Is As Good As A Rest
Hampshire Advertiser - Saturday 29 August 1857 - No author given
Ye votaries of sofas and beds
Ye sloths who exertion detest,
This maxim I wish to drive into your heads -
A change is as good as a rest.Ye children of Fashion and Wealth,
With countless indulgences blest,
Remember that indolence preyeth on health -
A change is as good as a rest.Ye sturdy old sons of the soil,
Who work through the day with such zest,
'Tis little ye have beside labour and toil;
But little of change or of rest.But ye of such leisure and cash
The sweets of employment should test;
To lavish your time is degrading and rash -
A change is as good as a rest.That porter just over the road,
Of this bit of knowledge posess'd,
From shoulder to shoulder is shifting his load -
A change is as good as a rest.That student, in sciences deep,
(With time's sterling value impress'd)
Now turns to My Novel, not thinking of sleep -
A change is as good as a rest.That merchant gets up with the lark,
His duties are aught but a jest;
These over, he rides with his son in the park -
A change is as good as a rest.My wife, in the kitchen below,
For dinner provideth her best,
Then crochets a nightcap for "dear little Flo" -
A change is as good as a rest.More relish of life is decreed
For all who this truth have confess'd-
Who grants it in heart, and confirms it in deed -
A change is as good as a rest.They have no Utopian desires,
Their spirits are seldom depress'd
Well-occupied leisure contentment inspires -
A change is as good as a rest.Mark I then, fellow-mortals around,
All ye who would wish to be blest,
Much wisdom in this simple phrase may be found -
A change is as good as a rest.
The poem states that it is specifically trying to popularise the phrase. It does not seem to have been very successful. The next occurrence of the phrase according to that site's search engine was in the Cornishman of 28 Jan 1897, forty years later. Google finds no occurrences of the first line of the second verse, anywhere.
OED doesn't mention Conan Doyle. It does have a similar saying which it dates from 1825:
1825 Christian Gleaner Mar. 62 Change of work is as good as play.
And it attributes the exact form to a rhyme in an American publication, again from before Conan Doyle was born:
1857 Defiance (Ohio) Democrat 26 Sept. 1/1 Ye votaries of sofas and beds—Ye sloths who exertion detest, This maxim I wish to drive into your heads—A change is as good as a rest.