It ought likewise to be considered, that very little of chemistry can be learned in a first course, which is hardly sufficient to make the language of the science familiar to the ears, or the apparatus familiar to the eyes. It is almost impossible to become a chemist in less than three or four years of constant application.
Elements of Chemistry in a New Systematic Order - Preface of the Author (p. xix), Printed for William Creech. Edinburgh, Scotland. 1790