This section is from the book "Popular Law Library Vol7 Equity Jurisprudence, Trusts, Equity Pleading", by Albert H. Putney. Also available from Amazon: Popular Law-Dictionary.
This form of equitable relief is limited to contracts for the sale of property, and contracts for insurance. There can be no specific performance of contracts for personal services, partnership contracts, contracts to marry, or contracts for the payment of a sum of money.
The specific performance of a contract for the payment of money, would be identical in its effect with that of a judgment at law for damages. The compelling by judicial decree of the specific performance of a contract to marry would be in violation of the ideas and principles of modern society.