viewed by the weekly London journal
_Engineering_,[82] and it was given lengthy notice by the rival journal,
_The Engineer_. The editor of _The Engineer_ thought that the
mechanician would find in it many new ideas, that he would be "taught to
detect hitherto hidden resemblances, and that he must part--reluctantly,
perhaps--with many of his old notions." "But," added the editor with
considerable justice, "that he [the mechanician] would suddenly
recognize in Professor Reuleaux's 'kinematic notation,' 'analysis,' and
'synthesis,' the long-felt want of his professional existence we do not
for a moment believe."[83] Indeed, the fresh and sharp ideas of Reuleaux
were somewhat clouded by a long (600-page) presentation; and his
kinematic notation, which required another attempt at classification,
did not simplify the presentation of radically new ideas.[84]

[Footnote 82: _Engineering_, _loc. cit._ (footnote 77).]

[Footnote 83: _The Engineer_, London, March 30 and April 13, 1877, vol.
43, pp. 211-212, 247-248.]

[Footnote 84: It is perhaps significant that the first paper of the
First Conference on Mechanisms at Purdue University was Allen S. Hall's
"Mechanisms and Their Classification," which appeared in _Machine
Design_, December 1953, vol. 25, pp. 174-180. The place of
classification in kinematic synthesis is suggested in Ferdinand
Freudenstein's "Trends in Kinematics of Mechanisms," _Applied Mechanics
Reviews_, September 1959, vol. 12, pp. 587-590.]

[Illustration: Figure 31.--Alexander Blackie William Kennedy
(1847-1928), translator of Reuleaux' _Theoretische Kinematik_ and
discoverer of Kennedy's "Law of Three Centers." From _Minutes of the
Proceedings of the Institution of Civil Engineers_ (1907, vol. 167,
frontispiece).]

Nevertheless, no earlier author had seen the problem of kinematic
analysis so clearly or had introduced so much that was fresh, new, and
of lasting value.

Reuleaux was first to state the concept of the pair; by his concept of
the expansion of pairs he was able to show similarities in mechanisms
that had no apparent relation. He was first to recognize that the fixed
link of a mechanism was kinematically the same as the movable links.
This led him to the important notion of inversion of linkages, fixing
successively the various links and thus changing the function of the
mechanism. He devoted 40 pages to showing, with obvious delight, the
kinematic identity of one design after another of rotar