Very many languages, as might be expected, contain special numeral expressions, such as the German _dutzend_ and the French _dizaine_; but these, like the English _dozen_ and _score_, are not to be regarded as numerals proper.
The formation of numeral words shows at a glance the general method in which any number scale has been built up.

The primitive savage counts on his fingers until he has reached the end of one, or more probably of both, hands.

Then, if he wishes to proceed farther, some mark is made, a pebble is laid aside, a knot tied, or some similar device employed to signify that all the counters at his disposal have been used.

Then the count begins anew, and to avoid multiplication of words, as well as to assist the memory, the terms already used are again resorted to; and the name by which the first halting-place was designated is repeated with each new numeral.
Hence the thirteen, fourteen, fifteen, etc., which are contractions of the fuller expressions three-and-ten, four-and-ten, five-and-ten, etc.

The specific method of combination may not always be the same, as witness the _eighteen_, or eight-ten, in English, and _dix-huit,_ or ten-eight, in French; _forty-five_, or four-tens-five, in English, and _fuenf und vierzig_, or five and four tens in German.