An ulterior disposition of the kind contemplated by the last preceding section cannot take effect unless the condition is strictly fulfilled.

Illustration.

   A transfers Rs. 500 to B, to be paid to him on his attaining his majority or marrying, with a proviso that, if B dies a minor or marries without C's consent, the Rs. 500 shall go to D. B marries when only 17 years of age, without C's consent. The transfer to D takes effect.