More than a few of your contributors have, I trust, concurred with me in hoping, if not expecting, that something will be done to effect the object presented to our notice through M.'s most judicious suggestion. It will be admitted that now, for about thirty years, the study of the history of early printing has been commonly neglected, frequently despised. The extent of the advance or decline of any science in general estimation can always be accurately computed by means of a comparative view of the prices demanded at different periods for the works which treat of it; and it is unquestionable, that books on bibliography, which once were highly rated, have latterly become (at least to those who have them already) provokingly cheap. In fact, unless some measures be adopted to revive a taste for this important branch of learning, the next generation will be involved in decrepitude and darkness with respect to typographical antiquities.
M. has incidentally asked, "Do different books circulate under the title of Fasciculus Temporum?" I should say, strictly speaking, Certainly not. But there is a sense in which the supposition is perfectly true; for we not only meet with the genuine Fasciculus of 1474, by Wernerus Rolevinck de Laer, but have also to encounter the same work as it was interpolated by Heinricus Wirezburg de Vach, and published for the first time in 1481. Ratdolt's edition of 1484, which M. used, does not contain the remarkable substituted passage in which the author was compelled to record the invention, instead of the propagation, of printing; and it would appear, therefore, that that impression does not belong to the Wirezburgian class. I have been surprised at finding that Pistorius and Struvius have reprinted the sophisticated, and not the authentic, book; and it is curious to see the introduction of an "&c." along with other alterations in the account given of the death of Henry VII. from the reception of a poisoned Host.
M. will instantly perceive that we cannot safely trust in a Fasciculus Temporum of, or after, the date 1481; but I can answer for the agreement of the impression of Colon. 1479 with the editio princeps. The citations respecting the Gutenberg Bible are not from the Fasciculus Temporum, but from Die Cronica van der hilliger Stadt van Coellen, A.D. 1499; the testimony of which (or rather of Ulric Zell related therein) as to the origin of printing is very well known through the Latin translation of it supplied by B. de Mallinckrot. (Clement, vii. 221.; Meerman, ii. 105.; Marchand, Hist. de l'Imp., ii. 4. 104.; Lambinet, 132.)
THE PENDULUM DEMONSTRATION, ETC.
(Vol. iv., pp. 129. 177. 235.)
It would have been more courteous in H. C. K. to have requested me to exhibit my authority for the assertion that the pendulum phenomenon had been latterly attributed to differences in the earth's superficial velocity, than to have assumed that explanation as having originated with myself. There is certainly nothing to justify H. C. K. in calling it "A. E. B.'s theory;" on the contrary, my avowed object was to suggest objections to it, and even my approval of it was limited to this, that, providing certain difficulties in it could be removed, it would then become the most reasonable explanation as yet offered of the alleged phenomenon,—the only one, I might have added, that I had the slightest hope of comprehending.
I can understand what is meant by the parallelism of the earth's axis; and, with the slight exceptions caused by precession and nutation, I take that to be the standard of fixity of direction in space. When, therefore, I am told that the plane of a pendulum's oscillation is also fixed in direction, and yet that it is continually changing its relative position with respect to the other fixity, the axis of the earth, not only does it not present to my mind a comprehensible idea, but it does present to it a palpable contradiction of the commonest axiom of philosophy.
I am therefore in a disposition of mind the reverse of H. C. K.'s; that which to him is only "hard enough to credit," to me is wholly incomprehensible; while that which to him is "utterly impossible to conceive," appears to me a rational hypothesis in which I can understand at least the ground of assertion.
H. C. K. asks me to "reduce to paper" the assertion of the difference of velocity between two parallels of latitude ten feet apart. He is not surely so unphilosophical as to imagine that a theory, to be true, must necessarily be palpable to the senses. If the element of increase exist at all, however minute and imperceptible it may be in a single oscillation, repetition of effect must eventually render it observable. But I shall even gratify H. C. K., and inform him that the difference in linear circumference between two such parallels in the latitude of London would be about fifty feet, so that the northern end of a ten-feet rod, placed horizontally in the meridian, would travel less by that number of feet in twenty-four hours than the southern end. This, so far from being inadequate, is greatly in excess of the alleged apparent motion in the plane of a pendulum's vibration.
In the remarks of another correspondent, E. H. Y. (Vol. iv., p. 177.), there is but one point that seems to require observation from me; it is his assertion that "there is no force by which a body unconnected with the earth would have any tendency to rotate with it!" Is then the rotation of forty miles of atmosphere, "and all that it inherit," due to friction alone? And even so, can any object, immersed in that atmosphere, be said to be "unconnected with the earth"?