“But Professor Harrison, in a paper read before the Royal Irish Academy in 1847, has stated that on careful examination of the head of an elephant which he had dissected, he could “see no evidence of the muscular structure if the membrana tympani so accurately described by Sir Everhard Home,” whose deduction is clearly inconsistent with the fact that the power of two elephants may be steadily combined by singing to them a measured chant, somewhat resembling a sailor's capstan song; and in labour of a particular kind, such as hauling a stone with ropes, they will thus move conjointly a weight to which their divided strength would be unequal.”
[Ceylon, Tennent, Vol.II, 1859]