Where a trust is incapable of being executed, or where the trust is completely executed without exhausting the trust-property, the trustee, in the absence of a direction to the contrary, must hold the trust-property, or so much thereof as is unexhausted, for the benefit of the author of the trust or his legal representative.
     Illustrations
     (a) A conveys certain land to B--
         "upon trust", and no trust is declared; or
         "upon trust to be thereafter declared", and no such declaration is ever made; or
         upon trusts that are too vague to be executed; or
         upon trusts that become incapable of taking effect; or
         "in trust for C", and C renounces his interest under the trust.
         In each of these cases B holds the land for the benefit of A.
     (b) A transfers Rs. 10,000 in the four per cents. to B, in trust to pay the interest annually accruing due to C for her life. A dies. Then C dies. B holds the fund for the benefit of A's legal representative.
     (c) A conveys land to B upon trust to sell it and apply one moiety of the proceeds for certain charitable purposes, and the other for the maintenance of the worship of an idol. B sells the land, but the charitable purposes wholly fail, and the maintenance of the worship does not exhaust the second moiety of the pro ceeds. B holds the first moiety and the part unapplied of the second moiety for the benefit of A or his legal representative.
     (d) A bequeaths Rs. 10,000 to B, to be laid out in buying land to be conveyed for purposes which either wholly or partially fail to take effect. B holds for the benefit of A's legal representative the undisposed of interest in the money or land if purchased.