Allowance
A foundry phrase, of general application. For example: some portion of a mould or core is scraped or filed away to prevent actual contact of two friable surfaces when closing a mould is called allowance, or clearance. A small proportion of zinc, over and above the recognized formula, to compensate for what is lost by volatilization during the process of mixing, is allowance. In fact, anything performed with the view of minimizing the possibilities of destroying the result of his labor, is recognized by the moulder as making allowance for such contingencies.