It's from "The Case for Classicism" by Lovecraft.
The first thing one remarks on reading his frigid “Engineering English” is its laconic atmosphere of aloofness from vivid feeling and from love of pure harmonic beauty.
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using or involving the use of a minimum of words : concise to the point of seeming rude or mysterious
So basically, it's indicating this piece doesn't require a lot of words to express itself. "Laconic" also tends to imply that this terseness is intentional.