1945 book The Gag Bag by Harry Stanley, most of whose books - both as writer and publisher - were for magicians. This is specifically for magic acts. He writes:
Many years ago Professor Hoffmann pointed out that patter which fits the personality of one type of magician, is by no means certain to suit other types... Magic has long been following a distinct trend in the direction of comedy. Magicians today are usually less solemn than the wizards of Hoffmann's time…every successful conjurer now injects some humour into his work -here then are some 'injections' which will arouse an audience to laughter.
The first few pages are about a 'Comedy Mind Reading Act' -the rest of the book is devoted to patter - jokes to warm up an audience, to fill the gaps when the conjurer is preparing his act etc.,
Of course, I never dare let my people know I was a magician. It would shock them. They think I'm still in prison.
I used to be a wallflower, until I took up magic. Now everybody asks me out. The other night at a show, I had only done one trick, and I was asked out.
There are only two kinds of conjurer you can't trust – the ones with moustaches and the clean-shaven ones.
He is a magician. His brother doesn't work either.
[Spoonerist patter] – 'my next disaster piece' (masterpiece) 'my next misery' (mystery) 'I will now utter the tragic words' (magic words.)
Public house catches fire... 50 magicians homeless.
Will someone call out any number between 16 and 60? Thank you I only wanted to find out if anyone was still awake.
These blades are very sharp – we can't afford to have anything dull on this programme.
This is the best milk I could get (pass the bottle or jug of milk, across your face three or four times) – PASTEURISE.
I call this a heavenly trick – I do it the milky way.
(For quiet audiences.) I know you're out there, because I can hear you breathing.
I wrote to Ripley about the next act (or trick), and he wrote back – I don't believe it.
He met her in a revolving door, and they went around together awhile.
I can't sleep at night. Was advised to count sheep. Last night I counted sheep up to 120,499 – and then I found it was time to get up.
I hear a sound from the back, I don't think it's applause.