NOTES.
1 (P. 5.) This letter is dated June 30, 1784, and others, written before the specification was drawn up, extend as far as the 22nd July of the same year. The specification is, however, dated April 28th, 1784, an inconsistency in Muirhead which seems to require explanation.
2 (P. 9.) Through 113 chapters he is compelled to employ long descriptions for what we express by the word pump. For example: Chap. 1:— "Cette cy est une sorte de machine, par laquelle facilement et sans point de bruit l'on peut faire monter l'eau d'une fontaine ou d'un fleuve à une proportionnée haulteur .... Chap. xvii.: Ceste autre façon de machine, par laquelle l'on faict pareillement monter l'eau d'un lieu des en hault .... Chap. lvii.: L'effect de ceste autre façon de machine est de faire monter l'eau d'un canal à une juste haulteur," etc.
3 (P. 11.) Calcul de l'Effet des Machines.
4 (P. 11.) Introduction a la Mécanique Industrielle.—Compare also § 129, Chap xii. of this work.
5 (P. 12.) From a philological point of view, "Kinematics" is incorrect,—Ampère should rather have said "Kinetics," (Cinétique). [It is of course impossible to make any alteration in this direction now in this country, where the word Kinetics has already obtained extended use in another sense, and there are good reasons for not making any change on the Continent, although the word Kinetics has not yet come into general use there.] It is in every way better to use the word with a K, as in the language from which it has been derived, than with the C which it owes to its transmission through the Latin and French.
6 (P. 21.) Parerga ii., Chap. iii., § 41, also Wille und Vorst. ii., Chap. xiv.
7 (P. 35.) It is very remarkable, and has long ago given occasion for reflection, that we so seldom find definitions of the machine which agree with each other. The following examples show how uncertain, and often how altogether indefinite, have been the attempts made to define the machine even by those who must have known the thing itself.
Weisbach. "Machines are all those artificial arrangements, by means of which forces are made to act in a way differing from that in which they would
