The Notebooks of Leonardo Da Vinci — Complete
the XVIth century, any maps at all approaching these in accuracy and
finish._
_The interesting map of the world, so far as it was then known,
which is among the Leonardo MSS. at Windsor (published in the_
'Archaeologia' _Vol. XI) cannot be attributed to the Master, as the
Marchese Girolamo d'Adda has sufficiently proved; it has not
therefore been reproduced here._
_Such of Leonardo's observations on places in Italy as were made
before or after his official travels as military engineer to Cesare
Borgia, have been arranged in alphabetical order, under Nos.
1034-1054. The most interesting are those which relate to the Alps
and the Appenines, Nos. 1057-1068._
_Most of the passages in which France is mentioned have hitherto
remained unknown, as well as those which treat of the countries
bordering on the Mediterranean, which come at the end of this
section. Though these may be regarded as of a more questionable
importance in their bearing on the biography of the Master than
those which mention places in France, it must be allowed that they
are interesting as showing the prominent place which the countries
of the East held in his geographical studies. He never once alludes
to the discovery of America._
I.
ITALY.
Canals in connection with the Arno (1001-1008).
1001.
CANAL OF FLORENCE.
Sluices should be made in the valley of la Chiana at Arezzo, so that
when, in the summer, the Arno lacks water, the canal may not remain
dry: and let this canal be 20 braccia wide at the bottom, and at the
top 30, and 2 braccia deep, or 4, so that two of these braccia may
flow to the mills and the meadows, which will benefit the country;
and Prato, Pistoia and Pisa, as well as Florence, will gain two
hundred thousand ducats a year, and will lend a hand and money to
this useful work; and the Lucchese the same, for the lake of Sesto
will be navigable; I shall direct it to Prato and Pistoia, and cut
through Serravalle and make an issue into the lake; for there will
be no need of locks or supports, which are not lasting and so will
always be giving trouble in working at them and keeping them up.
And know that in digging this canal where it is 4 braccia deep, it
will cost 4 dinari the square braccio; for twice the depth 6 dinari,
if you are making 4 braccia [Footnote: This passage is illustrated
by a slightly sketched map, on which these places are indicated from
West to East: Pisa, Luccha, Lago, Seravalle, Pistoja, Prato,
Firenze.] and there are but 2 banks; that is to say one from the
bottom of the trench to the surface of the edges of it, and the
other from these edges to the top of the ridge of earth which will
be raised on the margin of the bank. And if this bank were of double
the depth only the first bank will be increased, that is 4 braccia
increased by half the first cost; that is to say that if at first 4
dinari were paid for 2 banks, for 3 it would come to 6, at 2 dinari
the bank, if the trench measured 16 braccia at the bottom; again, if
the trench were 16 braccia wide and 4 deep, coming to 4 lire for the
work, 4 Milan dinari the square braccio; a trench which was 32
braccia at the bottom would come to 8 dinari the square braccio.
1002.
>From the wall of the Arno at [the gate of] la Giustizia to the bank
of the Arno at Sardigna where the walls are, to the mills, is 7400
braccia, that is 2 miles and 1400 braccia and beyond the Arno is
5500 braccia.
[Footnote: 2. _Giustizia_. By this the Porta della Giustizia seems
to be meant; from the XVth to the XVIth centuries it was also
commonly known as Porta Guelfa, Porta San Francesco del Renaio,
Porta Nuova, and Porta Reale. It was close to the Arno opposite to
the Porta San Niccolo, which still exists.]
1003.
By guiding the Arno above and below a treasure will be found in each
acre of ground by whomsoever will.
1004.
The wall of the old houses runs towards the gate of San Nicolo.
[Footnote: By the side of this text there is an indistinct sketch,
resembling that given under No.973. On the bank is written the word
_Casace_. There then follows in the original a passage of 12 lines
in which the consequences of the windings of the river are
discussed. A larger but equally hasty diagram on the same page
represents the shores of the Arno inside Florence as in two parallel
lines. Four horizontal lines indicate the bridges. By the side these
measures are stated in figures: I. (at the Ponte alla Carraja):
_230--largho br. 12 e 2 di spoda e 14 di pile e a 4 pilastri;_ 2.
(at the Ponte S. Trinita); _l88--largho br. 15 e 2 di spode he 28
di pilastri for delle spode e pilastri so 2;_ 3. (at the Ponte
vecchio); _pote lung br. 152 e largo;_ 4. (at the Ponte alle
Grazie): _290 ellargo 12 e 2 di spode e 6 di pili._
There is, in MS. W. L. 2l2b, a sketched plan of Florence, with the
following names of gates:
_Nicholo--Saminiato--Giorgo--Ghanolini--Porta San Fredian
--Prato--Faenza--Ghallo--Pinti--Giustitia_.]
1005.
The ruined wall is 640 braccia; 130 is the wall remaining with the
mill; 300 braccia were broken in 4 years by Bisarno.
1006.
They do not know why the Arno will never remain in a channel. It is
because the rivers which flow into it deposit earth where they
enter, and wear it away on the opposite side, bending the river in
that direction. The Arno flows for 6 miles between la Caprona and
Leghorn; and for 12 through the marshes, which extend 32 miles, and
16 from La Caprona up the river, which makes 48; by the Arno from
Florence beyond 16 miles; to Vico 16 miles, and the canal is 5; from
Florence to Fucechio it is 40 miles by the river Arno.
56 miles by the Arno from Florence to Vico; by the Pistoia canal it
is 44 miles. Thus it is 12 miles shorter by the canal than by the
Arno.
[Footnote: This passage is written by the side of a map washed in
Indian ink, of the course of the Arno; it is evidently a sketch for
a completer map.
These investigations may possibly be connected with the following
documents. _Francesco Guiducci alla Balia di Firenze. Dal Campo
contro Pisa_ 24 _Luglio_ 1503 (_Archivio di Stato, Firenze, Lettere
alla Balia_; published by J. GAYE, _Carteggio inedito d'Artisti,
Firenze_ 1840, _Tom. II_, p. 62): _Ex Castris, Franciscus
Ghuiduccius,_ 24. _Jul._ 1503. _Appresso fu qui hieri con una di V.
Signoria Alexandro degli Albizi insieme con Leonardo da Vinci et
certi altri, et veduto el disegno insieme con el ghovernatore, doppo
molte discussioni et dubii conclusesi che l'opera fussi molto al
proposito, o si veramente Arno volgersi qui, o restarvi con un
canale, che almeno vieterebbe che le colline da nemici non
potrebbono essere offese; come tucto referiranno loro a bocha V. S._
And, _Archivio di Stato, Firenze, Libro d'Entrata e Uscita di cassa
de' Magnifici Signori di luglio e agosto_
1503 _a_ 51 _T.: Andata di Leonardo al Campo sotto Pisa. Spese
extraordinarie dieno dare a di XXVI di luglio L. LVI sol. XII per
loro a Giovanni Piffero; e sono per tanti, asegnia avere spexi in
vetture di sei chavalli a spese di vitto per andare chon Lionardo da
Vinci a livellare Arno in quello di Pisa per levallo del lilo suo._
(Published by MILANESI, _Archivio Storico Italiano, Serie III, Tom.
XVI._} VASARI asserts: _(Leonardo) fu il primo ancora, che
giovanetto discorresse sopra il fiume d'Arno per metterlo in canale
da Pisa a Fiorenza_ (ed. SANSONI, IV, 20).
The passage above is in some degree illustrated by the map on Pl.
CXII, where the course of the Arno westward from Empoli is shown.]
1007.
The eddy made by the Mensola, when the Arno is low and the Mensola
full.
[Footnote: _Mensola_ is a mountain stream which falls into the Arno
about a mile and a half above Florence.
A=Arno, I=Isola, M=Mvgone, P=Pesa, N=Mesola.]
1008.
That the river which is to be turned from one place to another must
be coaxed and not treated roughly or with violence; and to do this a
sort of floodgate should be made in the river, and then lower down
one in front of it and in like manner a third, fourth and fifth, so
that the river may discharge itself into the channel given to it, or
that by this means it may be diverted from the place it has damaged,
as was done in Flanders--as I was told by Niccolo di Forsore.
How to protect and repair the banks washed by the water, as below
the island of Cocomeri.
Ponte Rubaconte (Fig. 1); below [the palaces] Bisticci and Canigiani
(Fig. 2). Above the flood gate of la Giustizia (Fig. 3); _a b_ is a
sand bank opposite the end of the island of the Cocomeri in the
middle of the Arno (Fig. 4). [Footnote: The course of the river Arno
is also discussed in Nos. 987 and 988.]
Canals in the Milanese (1009-1013).
1009.
The canal of San Cristofano at Milan made May 3rd 1509. [Footnote:
This observation is written above a washed pen and ink drawing which
has been published as Tav. VI in the _,,Saggio."_ The editors of
that work explain the drawing as _"uno Studio di bocche per
estrazione d'acqua."_]
1010.
OF THE CANAL OF MARTESANA.
By making the canal of Martesana the water of the Adda is greatly
diminished by its distribution over many districts for the
irrigation of the fields. A remedy for this would be to make several
little channels, since the water drunk up by the earth is of no more
use to any one, nor mischief neither, because it is taken from no
one; and by making these channels the water which before was lost
returns again and is once more serviceable and useful to men.
[Footnote: _"el navilio di Martagano"_ is also mentioned in a note
written in red chalk, MS. H2 17a Leonardo has, as it seems, little
to do with Lodovico il Moro's scheme to render this canal navigable.
The canal had been made in 1460 by Bertonino da Novara. Il Moro
issued his degree in 1493, but Leonardo's notes about this canal
were, with the exception of one (No. 1343), written about sixteen
years later.]
1011.
No canal which is fed by a river can be permanent if the river
whence it originates is not wholly closed up, like the canal of
Martesana which is fed by the Ticino.
1012.
>From the beginning of the canal to the mill.
>From the beginning of the canal of Brivio to the mill of Travaglia
is 2794 trabochi, that is 11176 braccia, which is more than 3 miles
and two thirds; and here the canal is 57 braccia higher than the
surface of the water of the Adda, giving a fall of two inches in
every hundred trabochi; and at that spot we propose to take the
opening of our canal.
[Footnote: The following are written on the sketches: At the place
marked _N: navilio da dacquiue_ (canal of running water); at _M:
molin del Travaglia_ (Mill of Travaglia); at _R: rochetta ssanta
maria_ (small rock of Santa Maria); at _A: Adda;_ at _L: Lagho di
Lecho ringorgato alli 3 corni in Adda,--Concha perpetua_ (lake of
Lecco overflowing at Tre Corni, in Adda,-- a permanent sluice). Near
the second sketch, referring to the sluice near _Q: qui la chatena
ttalie d'u peso_ (here the chain is in one piece). At _M_ in the
lower sketch: _mol del travaglia, nel cavare la concha il tereno
ara chotrapero co cassa d'acqua._ (Mill of Travaglia, in digging
out the sluice the soil will have as a counterpoise a vessel of
water).]
1013.
If it be not reported there that this is to be a public canal, it
will be necessary to pay for the land; [Footnote 3: _il re_. Louis
XII or Francis I of France. It is hardly possible to doubt that the
canals here spoken of were intended to be in the Milanese. Compare
with this passage the rough copy of a letter by Leonardo, to the
_"Presidente dell' Ufficio regolatore dell' acqua"_ on No. 1350. See
also the note to No. 745, 1. 12.] and the king will pay it by
remitting the taxes for a year.
Estimates and preparatory studies for canals (1014. 1015).
1014.
CANAL.