Can one person's invitation to touch another person's penis constitute an assault?

In Fairclough v. Whipp, supra, the facts were that the accused was charged with committing an indecent assault on a child of the age of nine. The question was whether there was an assault. The accused was “making water” by the bank of a river where there were four young girls varying in age from six to nine. As he did so, one of the girls passed him. He, with his person exposed, said to her, “Touch it” and she did so. He then went away. The question for decision was whether that conduct amounted to an indecent assault. Lord Goddard C.J. said at p. 834: An assault can be constituted, without there being battery, for instance by a threatening gesture or a threat to use violence against the person, but I do not know any authority which says that where one person invites another person to touch him that can be said to be an assault … I cannot hold that an invitation to somebody to touch the invitor can amount to an assault on the invitee … It seems to me there must be an act done to a person.