In a book written in 1832, Illustrations of Political Economy by Harriet Martineau, the author makes a reference to the idea of counting sheep as a means to help her fall asleep:
It was a sight of monotony to behold one sheep after another follow the adventurous one, each in turn placing its fore-feet on the breach in the fence, bringing up its hind legs after it, looking around for an instant from the summit, and then making the plunge into the dry ditch, tufted with locks of wool. The process might have been more composing if the field might have been another man’s property, or if the flock had making its way out instead of in; but the recollection of the scene of transit served to send the landowner to sleep more than once, when occurring at the end of the train of anxious thoughts which had kept him awake. (pg. 355–356)
Follow our advice and you will only get to only one sheep before falling right to sleep!