trees ac-5
cording to their colours (435).--The proportions of light and shade in trees (436--440).--The distribution of light and shade with reference to the position of the spectator (441--443).--The effects of morning light (444--448).--The effects of midday light (449).--The appearance of trees in the distance (450--451).--The cast shadow of trees (452. 453).--Light and shade on groups of trees (454--457).--On the treatment of light for landscapes (458--464).--On the treatment of light for views of towns (465--
469).--The effect of wind on trees (470--473).--Light and shade on clouds (474--477).--On images reflected in water (478).--Of rainbows and rain (479. 480).--Of flower seeds (481).
IX.
THE PRACTICE OF PAINTING
I. MORAL PRECEPTS FOR THE STUDENT OF PAINTING.--How to ascertain the dispositions for an artistic career (482).-- The course of instruction for an artist (483--485).--The study of the antique (486. 487).--The necessity of anatomical knowledge (488. 489).--How to acquire practice (490).--Industry and thoroughness the first conditions (491--493.)--The artist's private life and choice of company (493. 494).--The distribution of time for studying (495-- 497).--On the productive power of minor artists (498--501).--A caution against one-sided study (502).--How to acquire universality (503--506).--Useful games and exercises (507.
508).--II. THE ARTIST'S STUDIO.--INSTRUMENTS AND HELPS FOR THE APPLICATION OF PERSPECTIVE.--ON JUDGING OF A PICTURE.--On the size of the studio (509).--On the construction of windows (510--512).--On the best light for painting (513--520).--On various helps in preparing a picture (521--530).--On the management of works (531. 532).--On the limitations of painting (533--535).--On the choice of a position (536. 537).--The apparent size of figures in a picture (538. 539).-- The right position of the artist, when painting and of the spectator (540--547).--III. THE PRACTICAL METHODS OF LIGHT AND SHADE AND AERIAL PERSPECTIVE.--Gradations of light and shade (548).--On the choice of light for a picture (549--554).--The distribution of light and shade (555--559).--The juxtaposition of light and shade (560. 561).--On the lighting
of the background (562--565).--On the lighting of white objects (566).--The methods of aerial perspective (567--570).--IV. OF PORTRAIT AND FIGURE PAINTING.--Of sketching figures and portraits (571. 572).--The position of the head (573).--Of the light on the face (574--576).--General suggestions for historical pictures (577--581).--How to represent the differences of
age and sex (582. 583).--Of representing the emotions (584).--Of representing imaginary animals (585).--The selection of forms (586--591).--How to pose figures (592).--Of appropriate gestures (593--600).--V. SUGGESTIONS FOR COMPOSITIONS.-- Of painting battle-pieces (601--603).--Of depicting night-scenes (604).--Of depicting a tempest (605. 606).--Of represent-
ing the deluge (607--609).--Of depicting natural phenomena (610. 611).--VI. THE ARTIST'S MATERIALS.--Of chalk and paper (612--617).--On the preparation and use of colours (618--627).--Of preparing the panel (628).--The preparation of oils (629--634).--On varnishes (635-- 637).--On chemical _materials (638--650).--VII. PHILOSOPHY AND HISTORY OF THE ART OF PAINTING.--The relation of art and nature (651. 652).--Painting is superior to poetry (653. 654).--Painting is superior to sculpture (655. 656).--Aphorisms (657--659).--On the history of painting (660. 661).--The painter's scope (662).
X.
STUDIES AND SKETCHES FOR PICTURES AND DECORATIONS
On pictures of the Madonna (663).--Bernardo di Bandino's portrait (664).--Notes on the Last Supper (665--668).--On the battle of Anghiari (669).--Allegorical representations referring to the duke of Milan (670--673).--Allegorical representations (674--
678).--Arrangement of a picture (679).--List of drawings (680).--Mottoes and Emblems (681--702). The author's intention to publish his MSS.
1.
How by a certain machine many may stay some time under water. And how and wherefore I do not describe my method of remaining under water and how long I can remain without eating. And I do not publish nor divulge these, by reason of the evil nature of men, who would use them for assassinations at the bottom of the sea by destroying ships, and sinking them, together with the men in them. Nevertheless I will impart others, which are not dangerous because the mouth of the tube through which you breathe is above the water, supported on air sacks or cork.
[Footnote: The leaf on which this passage is written, is headed with the words Casi 39, and most of these cases begin with the word
'Come', like the two here given, which are the 26th and 27th. 7. Sughero. In the Codex Antlanticus 377a; 1170a there is a sketch,
drawn with the pen, representing a man with a tube in his mouth, and at the farther end of the tube a disk. By the tube the word
'Channa' is written, and by the disk the word 'sughero'.]
6
The preparation of the MSS. for publication.
2.
When you put together the science of the motions of water, remember to include under each proposition its application and use, in
order that this science may not be useless.--
[Footnote: A comparatively small portion of Leonardo's notes on water-power was published at Bologna in 1828, under the title:
"Del moto e misura dell'Acqua, di L. da Vinci".]
Admonition to readers.
3.
Let no man who is not a Mathematician read the elements of my work. The disorder in the MSS.
4.
Begun at Florence, in the house of Piero di Braccio Martelli, on the 22nd day of March 1508. And this is to be a collection without order, taken from many papers which I have copied here, hoping to arrange them later each in its place, according to the subjects of which they may treat. But I believe that before I am at the end of this [task] I shall have to repeat the same things several times; for which, O reader! do not blame me, for the subjects are many and memory cannot retain them [all] and say: 'I will not write this because I wrote it before.' And if I wished to avoid falling into this fault, it would be necessary in every case when I wanted to copy [a passage] that, not to repeat myself, I should read over all that had gone before; and all the more since the intervals are long between one time of writing and the next.
[Footnote: 1. In the history of Florence in the early part of the XVIth century Piero di Braccio Martelli is frequently mentioned as Commissario della Signoria. He was famous for his learning and at his death left four books on Mathematics ready for the press; comp. LITTA, Famiglie celebri Italiane, Famiglia Martelli di Firenze.--In the Official Catalogue of MSS. in the Brit. Mus., New Series Vol. I., where this passage is printed, Barto has been wrongly given for Braccio.
2. addi 22 di marzo 1508. The Christian era was computed in Florence at that time from the Incarnation (Lady day, March 25th).
Hence this should be 1509 by our reckoning.
3. racolto tratto di molte carte le quali io ho qui copiate. We must suppose that Leonardo means that he has copied out his own MSS. and not those of others. The first thirteen leaves of the MS. in the Brit. Mus. are a fair copy of some notes on physics.]
Suggestions for the arrangement of MSS treating of particular subjects.(5-8).
5.
Of digging a canal. Put this in the Book of useful inventions and
