634. Liability for repayment where there are several mortgagors.

Mortgagors may either agree between themselves1 who is to be responsible for repayment2, or such an agreement may be inferred3. If they have had the benefit of the money in specific shares, or for the purpose of a joint adventure, they must contribute to the repayment of the debt in the proportions of their shares in the mortgage money4, or in the joint adventure5. Alternatively, one may have had the exclusive benefit of it, so as to be the principal debtor, while the others are sureties6, in which case the sureties are entitled to be exonerated by the principal