I'll present Speed's main points in boldface type either verbatim or paraphrased, followed by my comments. If you want to add a comment, please use the numbered points to refer to the relevant section of the chapter.
In this section of the chapter, Speed discusses the brushes for oil painters.
1. You can use cheaper paints when you're a student, but even if you're poor, you shouldn't skimp on brushes.
I totally agree with Speed on this one. He says "A cheap brush is useless from the start and has, luckily, a very short life as they wear very badly. The best brushes last much longer."
2. Cleaning brushes. "Soap and water cleans them most thoroughly and is the best way of cleaning them. But it is a most tedious process after a hard day's work."
Here's a previous post on "How to Clean out a Brush"
3. After washing them out, the brushes "should be lovingly sucked to bring the hairs together."
Never heard that one before. One would want to make sure to remove all the lead, cobalt, barium, and cadmium first. Or maybe pass on that idea.
4. "When thoroughly dry they have plenty of spring in them, whereas the slightest dampness gives them a flabbiness."
He's talking about bristle brushes here. It's really true. Damp brushes are flabbier.
5. Flats and Rounds: Flats are better for "laying a perfectly even tone, but give a nasty thin sharp edge...For figure work and form expression generally, one wants a brush that will lay the paint in even, flat tones without thin sharp edges."
He's referring to flat brushes with rounded corners, alternately the modern filbert
6. Fashion for soft haired brushes used for flowing strokes (in the 1920s).
Speed notes that some of the inspiration came from studying Frans Hals, who apparently used such brushes. Speed generally prefers stiffer hogs' hair bristles.
7. "Always work with the biggest brush that will do what you want."
Then choose the next size bigger. Speed notes that a big flat brush is really several brushes in one, because you can use the corner and the edge for very different strokes.
8. "The brush makers have an absurd habit of making the size of the handle fit the size of the brush, instead of the size of the hand that will have to hold it."
He continues, "Very small brushes need a very firm grip to control them as they are only used for very delicate work. And yet they are often given a handle no thicker than a match."
I totally agree, and I've always wondered about this, too. Pencils, pens, knives, and golf clubs have constant sized handles. Why don't brushes?
9. Only German brushes have an indented ring round the metal holder (ferrule) to prevent the tip falling off the handle.
Now crimped ferrules are pretty standard even on cheap brushes.
10. Cheap brushes "appear to have been sharpened off to make them a good shape, after being roughly put together; instead of the good shape being the result of a careful placing of the individual hairs."
Here's a video about how they make Escoda brushes
(Link to video)
More on brushes at:
MacPherson Arts / "Brush Basics"

-----
In its original edition, the book is called "The Science and Practice of Oil Painting
." Unfortunately it's not available in a free edition, but there's an inexpensive print edition that Dover publishes under a different title "Oil Painting Techniques and Materials
(with a Sargent cover)," and there's also a Kindle edition.
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7 Comments on Gurney Journey: Harold Speed Talks Brushes
There's a bit of info on this on the rather long wikipedia page about Van Gogh's health."
Apparently there is some science to spit being a good preserver of brushes. A retired doctor student/friend did a bit of research into it and said that there is a polymerization effect that happens-so it's not just tradition. The atelier I went to/taught at in florence had all students spitting into their hands to rub their brushes with at the end of each day. I always found it a bit gross, but apparently it works-until they get dirty again...
Also, I have known 2 older painters who suck on their brushes after washing them each session, just like Speed says. Obviously this is a bit scary, but they were each in their eighties and had been taking care of their brushes like that at the end of each session for many decades. Health concerns aside, a bit less gross than spitting in your hand perhaps?"
My studio is in my living space, so I'm likely to paint at almost anytime I'm awake. For that reason, I have to be careful to put my recently washed brushes well aside (even in a different room) until they're thoroughly dry so that I don't mistakenly grab them to paint with before they're dry. (Talking here about painting in oils.)"
https://www.facebook.com/media/set/?set=oa.931102893602685&type=1"
Once cleaned, some people place a small folded piece of cardboard, over the brush hairs, with a small clip to ensure the brush dries with a sharp chisel edge. I guess that would negate the need for spit!"
I used to use Dawn dish soap to wash my brushes, but discontinued that when I noted it dried them out too much.
Now after a quick rinse in spirits, I use Murphy's Oil Soap. Keeps the bristles soft and gets pigment out well."