About :: When, in consequence of a transfer, property is divided and held in several shares, and thereupon the benefit of any obligation relating to the property as a whole passes from one to several owners of the property, the corresponding duty shall, in the absence f a contract to the contrary amongst the owners, be performed in favour of each of such owners in proportion to the value of his share in the property, provided that the duty can be severed and that the severance does not substantially increase the burden of the obligation; but if the duty cannot be severed, or if the severance would substantially increase the burden of the obligation the duty shall be performed for the benefit of such one of the several owners as they shall jointly designate for that purpose: Provided that no person on whom the burden of the obligation lies shall be answerable for failure to discharge it in manner provided by this section, unless and until he has had reasonable notice of the severance. Nothing in this section applies