From Nonsense for Old and Young by Eugene Field, 1901.

Why is a jester associated with a cone?  We find our answer in Percy Bysshe Shelley's Oedipus Tyrannus, in which Swellfoot says, "Sustain the cone of my untroubled brain, / That point, the emblem of a pointless nothing!" (I.i.).

Our illustration is from an advertisement c. 1872.

"This nonsense must be stopped, he said."  From An African Millionaire by Grant Allen, 1897.

"Only clowns try to find suitable clothes. ... And they turn nonsense into a sacred rite. ... [E]ven Art often fails to do for us what a clown does.  Laughter and tears together. ... With his tragic clumsiness ... he lurches out over the reality that we have lost.  When he grasps for support he grasps at fantasies, and when he stumbles he falls out of the world altogether." —Ernst Kreuder, The Attic Pretenders

Don't forget Horse Nonsense, the Sellar & Yeatman book.
—Jonathan Caws-Elwitt

"Brown, our one earnest member, begged us to be reasonable, and reminded us, not for the first time, and not, perhaps, altogether unnecessarily, that these meetings were for the purpose of discussing business, not of talking nonsense."
—Jerome K. Jerome, Novel Notes

"Following the invention-of-tradition logic, monks’ consciousness about their musical tradition would disqualify it as genuinely traditional. This is problematic (read: nonsense), to say the least." —Tore Tvarnø Lin, The Past Is Always Present

"On a topographical map of Literature Nonsense would be represented by a small and sparsely settled country, neglected by the average tourist, but affording keen delight to the few enlightened travellers who sojourn within its borders." —Carolyn Wells, A Nonsense Anthology, 1910 (via Jonathan Caws-Elwitt)

"I told you to get into pictures!" Heffy huffed.  "Not this nonsense."
Mariel spoke up.  "Look, Sid, someone has to provide the nonsense, now that you’ve been called to a higher art."
—Jeremy Edwards, The Pleasure Dial