All Leonardo's precious manuscripts were bequeathed to Francesco Melzi, and unfortunately became scattered. About the end of the seventeenth century they were mostly in the Ambrosian Library at Milan; but the French under Napoleon took fourteen of the principal manuscripts, leaving only two, which now form the "Codex Atlantico" at Milan. The latter is a collection of four hundred of Leonardo's drawings and manuscripts. One volume on mathematics and physics is among the Arundel Manuscripts, at the British Museum. At Holkham is a manuscript of the _Libro Originali di Natura_. In 1651 Raphael Trichet Dupresne, of Paris, published a selection from Da Vinci's works on painting, the _Trattato della Pittura_, which has been reprinted twenty-two times in six different languages, "one of the best guides and counsellors of the painter." A "Treatise on the Motion and Power of Water" was published later. In 1883 Jean Paul Richter, Knight of the Bavarian Order of St. Michael, after years of labor over the strange handwriting of Da Vinci, from right to left across the page, published much of the work of the great painter, reproducing his sketches by photogravure. He had access to the manuscripts in the Royal Library at Windsor, the Institute of France, the Ambrosian Library at Milan, the Louvre, the Academy of Venice, the Uffizi, the Royal Library of Turin, the British and South Kensington Museums, and Christ Church College, Oxford. Richter says, "Da Vinci has been unjustly accused of having squandered his powers by beginning a variety of studies, and then, having hardly begun, thrown them aside. The truth is that the labors of three centuries have hardly sufficed for the elucidation of some of the problems which occupied his mighty mind." Leonardo's astronomical speculations, his remarks on fossils, at that time believed to be mere freaks of nature, his close study of botany, his researches in chemistry, color, heat, light, mechanics, anatomy, music, acoustics, and magnetism, have been an astonishment to every reader. Among his inventions were "a proportional compass, a lathe for turning ovals, an hygrometer; an ingenious surgical probe, a universal joint, dredging machines, wheelbarrows, diving-suits, a porphyry color-grinder, boats moved by paddle-wheels, a roasting-jack worked by hot air, a three-legged sketching-stool which folded up, a revolving cowl for chimneys, ribbon-looms, coining presses, saws for stone, silk spindles and throwers, wire-drawing and file-cutting, and plate-rolling machines." No wonder he was called the "all-knowing Leonardo." All his work as a poet is lost, save one sonnet:--