The numerous notes as to the laws and rationale of the flight of birds, are scattered through several note-books.  An account of these is given in the Bibliography of the manuscripts at the end of this work.  It seems probable that the idea which led him to these investigations was his desire to construct a flying or aerial machine for man.  At the same time it must be admitted that the notes on the two subjects are quite unconnected in the manuscripts, and that those on the flight of birds are by far the most numerous and extensive.  The two most important passages that treat of the construction of a flying machine are those already published as Tav.  XVI, No. 1 and Tav.  XVIII in the “Saggio delle opere di Leonardo da Vinci” (Milan 1872_).  The passages—­Nos._ 1120-1125—­here printed for the first time and hitherto unknown—­refer to the same subject and, with the exception of one already published in the Saggio—­ No. 1126—­they are, so far as I know, the only notes, among the numerous observations on the flight of birds, in which the phenomena are incidentally and expressly connected with the idea of a flying machine.

The notes on machines of war, the construction of fortifications, and similar matters which fall within the department of the Engineer, have not been included in this work, for the reasons given on page 26 of this Vol.  An exception has been made in favour of the passages Nos. 1127 and 1128, because they have a more general interest, as bearing on the important question:  whence the Master derived his knowledge of these matters.  Though it would be rash to assert that Leonardo was the first to introduce the science of mining into Italy, it may be confidently said that he is one of the earliest writers who can be proved to have known and understood it; while, on the other hand, it is almost beyond doubt that in the East at that time, the whole science of besieging towns and mining in particular, was far more advanced than in Europe.  This gives a peculiar value to the expressions used in No. 1127.

I have been unable to find in the manuscripts any passage whatever which throws any light on Leonardo’s great reputation as a musician.  Nothing therein illustrates VASARPS well-known statement: Avvenne che morto Giovan Galeazze duca di Milano, e creato Lodovico Sforza nel grado medesimo anno 1494, fu condotto a Milano con gran riputazione Lionardo al duca, il quale molto si dilettava del suono della lira, perche sonasse; e Lionardo porto quello strumento ch’egli aveva di sua mano fabbricato d’argento gran parte, in forma d’un teschio di cavallo, cosa bizzarra e nuova, acciocche l’armonia fosse con maggior tuba e piu sonora di voce; laonde supero tutti i musici che quivi erano concorsi a sonare.

The only notes on musical matters are those given as Nos. 1129 and 1130, which explain certain arrangements in instruments.