Not a Day Without a Line

Now without in any way daring to claim to rise as high as them, nevertheless, by continuing to draw these types of workmen &c., I’m confident of succeeding in becoming more or less capable of working in magazine or book illustration. First and foremost, when I’ll be able to pay more for models, and female models too, I’ll make further progress; I feel it and I know it. And I’ll probably also succeed in being able to do portraits. But that depends on working hard; not a day without a line, as Gavarni used to say.

Vincent van Gogh. From the letter to Theo van Gogh. Brussels, January 1881.
http://vangoghletters.org/vg/letters/let162/letter.html