There seems to be nothing crazy about bat “droppings”?
Instead bat “droppings” or guano, has a history of being important in agriculture and nothing of the sort in connection to the phrase? ([COLOR=#000000][FONT=sans-serif]8 to 12 percent equivalent phosphoric acid, and 2 to 3 percent equivalent [/FONT][/COLOR]potash[COLOR=#000000][FONT=sans-serif]. Bat and seal guano are lower in fertilizer value than bird guano.)[/FONT][/COLOR]
There is on wiktionary the phrase “have bats in one’s belfry” from 1899. And explains the original as the tendency of bats to fly around erratically?
But I find that as an explanation a bit far fetched?
Does bat guano make you ill?