In 1873 Marcq St Hilaire introduced the concept of the intercept method of constructing a position line, with the use of an assumed position chosen to facilitate calculation or tabulation. This same basic principle is here used to facilitate direct calculation without the use of logarithms or calculator; a simple table of a natural trigonometrical function is required and, preferably, some aid to multiplication. Apparently the method has not been proposed before, and it is ironic that it should be considered when the availability of calculators has essentially removed any requirement for it! It is put forward mainly for theoretical interest, but there may be a place for it for emergency use when (for some reason) neither conventional tables nor a calculator is available.