The Great Beast writes:

I witnessed a remarkable sight on the road to Chabanjong, which was here a paka rasta (that is, a road made by engineers as opposed to kacha rasta, a track made by habit or at most by very primitive methods) wide enough for carts to pass. I had squatted near the middle of the road as being the least damp and leech-infested spot available and got a pipe going by keeping the bowl under my waterproof. I lazily watched a leech wriggling up a blade of tall grass about fifteen inches high and smiled superiorily at its fatuity — though when I come to think of it, my own expedition was morally parallel; but the leech was not such a fool as I thought. Arrived at the top, it began to set the stalk swinging to and fro; after a few seconds it suddenly let go and flew clean across the road. The intelligence of and ingenuity of the creature struck me as astonishing. — The Confessions of Aleister Crowley: An Autohagiography (1929), ch. 52