A friend asked if I might "recommend a short text/ excerpt about time (preferably slowness)?" What came to mind was the fifth paragraph of Ambrose Bierce's short story "An Occurrence at Owl Creek Bridge" (1890), where Peyton Farquhar, about to be hanged...

"...closed his eyes in order to fix his last thoughts upon his wife and children. The water, touched to gold by the early sun, the brooding mists under the banks at some distance down the stream, the fort, the soldiers, the piece of drift--all had distracted him. And now he became conscious of a new disturbance. Striking through the thought of his dear ones was a sound which he could neither ignore nor understand, a sharp, distinct, metallic percussion like the stroke of a blacksmith's hammer upon the anvil; it had the same ringing quality. He wondered what it was, and whether immeasurably distant or near by--it seemed both. Its recurrence was regular, but as slow as the tolling of a death knell. He awaited each stroke with impatience and--he knew not why--apprehension. The intervals of silence grew progressively longer, the delays became maddening. With their greater infrequency the sounds increased in strength and sharpness. They hurt his ear like the thrust of a knife; he feared he would shriek. What he heard was the ticking of his watch."