Painters of the Newlyn School, a group of 19th century plein-air painters in southwestern England, were known for their “consistent squareness of touch.”
“A Street in Brittany” by Stanhope Forbes shows the characteristic look achieved by brushes that we would call brights or flats. Forbes once wrote home to his mother asking her to bring a “flat sable brush” when she came to visit.
Sir George Clausen (1852-1944) was also known for his square brush technique, which the British critics identified with French juste-milieu painters like Bastien-Lepage, with whom some of the Newlyn artists studied.
The purpose of the method was not just to get that chunky feeling, but to blur outlines and capture an atmospheric envelope. The critic Garstin wrote: “We seek to represent not only the man but, as it were, his very atmosphere, and not only his surroundings, but his surroundings under certain specific conditions.”
Other artists indentified with a square touch are Arthur Streeton, Frank Brangwyn, and Dean Cornwell.
Reference for quotes: Artists of the Newlyn School, 1880-1900, by Caroline Fox, 1979, link.
Images from FreeParking's Flickr stream, link.