In his preface, he explains that the term refers to "a body of knowledge that is easier to list than to bring together under a precise definition". He then notes that the list in the title of his book makes up for "whatever shortcomings this definition may have": "Dictionnaire des mathématiques appliquées, covering the principal applications of mathematics to architecture, commercial arithmetic, surveying, artillery, insurance, ballistics, banking, carpentry, railways, etc., etc."
This list, already some thirty items long, is continued in this issue with numerous examples from Sonnet's present-day successors.
