This note, which may be found almost identical on sheet 33 r. of the Leicester manuscript and which
undoubtedly precedes it (both because the sheet mentioned by the K manuscript was initially written
quickly in pencil and then rewritten in pen, and because it is clear that the single observations were copied
from a small pocket book, which the K manuscript was, to the Leicester manuscript, rather than the
other way round),
Observe, as confirmation, the arrangement of the words and the completion of the note in the Leicester manuscript.
is the last clue which, at the present state of investigation (save what was mentioned hypothetically,
about 1506, on pages 14 and 15), suggests it probable that the Leicester manuscript or at least most of
it was written between 1504 and 1506, with some reasons for preferring the two year period 1505-6. Those
subjects in common which would seem almost to exclude a continuous investigation of some topics, from
the last sheets (in terms of time) of the Leicester manuscript and the first (still kept, as we have said, in the
original order) of the Arundel Codex and then the manuscript F, would leave room for the hypothesis that
the Leicester Codex may, rather, not have been begun until the later Florentine period 1507-1508; the same
in which the Arundel Codex was begun in Piero di Braccio Martelli’s house.
This seems possible but much less probable; while the theory that Leonardo wrote a part (not more than
the last third) of the manuscript after he had been to Milan in 1506 may have some grounds, or that leaving
Florence with a pass that would not have been for a period longer than three months according to the pacts
imposed by the Florentine Seignoury, he left in Florence or deposited in Vinci (if the objection already raised
in note. 7 on page 15, did not prevent one from thinking that he still had a safe house there) a part of his
furnishings, books and manuscripts; and with them the Leicester manuscript (given that Leonardo did not
believe it essential for him to have this book on water with him during his brief stay in Lombardy), which
could have been finished upon his return to Florence.
From the approximate conclusions at which one arrives, the deductions that might be made on the series
of relations existing between the Leicester manuscript and the other Vinci codex would seem to concur,
both as regards the derivation of the subjects and as regards the succession and development of the ideas.
One could enter into the course of comparative considerations, if in this case the work did not take on proportions
which would make it an end in itself,
requiring
We shall limit ourselves to pointing out the coincidences which seem most striking and which may be observed in brief notes. The
interesting observations on sheet 35 r. on the ebb and flow observed in two channels which collided and merged are to be compared
with the sketch and note on sheet 67 v. of the M manuscript (which Richter (op. cit, I, pg. 6) ascribes to 1515 circa, but which may
actually have been written at an earlier date between the I and K manuscripts (1497-1507 circa); cf. also the W. L. manuscript 141 r., in
Richter, op. cit., II, pg. 432, § 1436. The sketch and note on sheet 5r.-a of the Atlantic Codex (which also has, on sheet 5 v.-a, the
drawing of the roasting-spit mentioned on sheet 28 v. and the other minimal sketch on sheet 384 v.-b of the Atlantic Codex) correspond
to the method for weighing falling water indicated on sheet 23v. The principle (sheet 26 v.) of the division ad infinitum of the wine poured
from a vessel to which water is continually added, may be found again on sheets 218 r.-b and 247 v.-a of the Atlantic Codex where
it is the object of detailed calculations. The drawings and considerations on the methods of driving in stakes to make a frame (sheet 10
v.), are to be compared to sheets 74 r.-73 v. [85 v.-86 r. according to Leonardo’s numeration] of the Forster II manuscript (cf. also manuscript
B, sheets 69 v., 70 r. and ms. H, 80 v., 81 r.). The table da giuocare drawn on sheet 4 v. “per prova dell’onda spuntellata” [For
proof of the wave that is clipped] have already been used for an experience on sheet 55 r. of manuscript A; and the isolated figure,
which is below the note relative to them, is found in only slightly varied proportions, on sheets 348 r.-a (in the period of his youth) and
241 r.-a of the Atlantic Codex; on this last sheet, with the following note beside it: “I particulari concludano li universali”[The details
confirm the rule]. Other comparisons may serve to clarify some points of the Leicester manuscript. In the notes to sheet 28 r.-a comparison
is proposed with sheet 169 r.-a of the Atlantic Codex, so as to better clarify a passage of Leonardo’s on the wind; on the same
subject, compare sheet 12 v. ( and fig. 9a) of the Leicester manuscript (as well as sheet 28 r., cit.) with sheets 130 [82] v. of the I manuscript
and sheets 180 v.-a and 200 v.-a of the Atlantic Codex, noting the correspondence of the figures. The strange note on sheet 19 r.,
on the ullage to be given to the water is better explained when compared to the fragment of the Atlantic Codex already indicated in note
2 on pg. 19. Sheets 10 v., 32 v., 60 v.-62 r. of the B manuscript show how rivers should be crossed by armies (Leicester manuscript,
sheet 22 v., where mention is also made of how to stay underwater; see in this regard the pages of Leonardo commented on by Baratta
in Curiosità vinciane, Turin, Bocca, 1905, pg. 111-199).
Lastly, we will observe how, on the highly interesting note on sheet 15 v.: “Come si po fare montare le barche contro alle sommità de’
monti, se di lassù discende alcuna parte d’acqua” [how boats may be made to lie on the top of the mountain if some water descends from
there] (and for the corresponding note in the list of subjects in the treatise on sheet 74 r.-a of the Atlantic Codex: “Del condurre le barche
nelli alti monti per canali d’acque”) [On taking boats into the high mountains by means of canals of water] one may find some comments
on sheet 46 v.-b of the Atlantic Codex ( later also examining sheet 108 v.-a of the Atlantic Codex and sheet 26 r. of the B manuscript). In
these Leonardo appears, as he does in the Leicester manuscript, as the prophet announcing the most daring challenges of the modern age,
putting the triumphant aviators on the same footing as the brilliant Italian inventor who had in recent years proposed a gigantic network
of navigable waterways through the Alps.
an exhaustive investigation incompatible with the
