Treatises on machines
The fifteenth century saw an increased output of treatises dedicated to illustrations of machines. Taccola and Francesco di Giorgio, among others, prepared illustrated texts showing an attempt to combine a revival of classical technology with the development of innovative methods and processes.
The manuscripts of Taccola
Books I and II of De ingeneis, written between 1419 and 1450, are the oldest surviving texts of Taccola. The autograph manuscript, today in Munich, contains texts and drawings relating to civil and military engineering and hydraulic devices, along with quotations from ancient authors.
Books III and IV of De ingeneis, written between 1431 and 1433, are today in Florence. The main subject of the drawings, generally placed on facing pages, is hydraulics.
The De machinis, now in Munich, dates from 1430-49. It chiefly deals with military topics.
The manuscripts of Francesco di Giorgio
The earliest known manuscript of Francesco di Giorgio, dating from 1465-70, is the Codicetto in the Vatican Library.
The Opusculum de architectura, now in London, dates from 1475-80 and is dedicated to Federico da Montefeltro. It contains magnificent drawings of machines and mechanical systems.
Francesco di Giorgio later drafted a Treatise of which the two surviving copies date from 1480. The text deals with architectural and engineering topics. A later version of the Treatise exists in a Florentine manuscript dating from around 1490.
The impact of the manuscripts of Sienese engineers
Even though they never went to the printer's, the manuscripts of Taccola and Francesco enjoyed a tremendous success. Scores of sixteenth-century manuscripts contain illustrations of machines designed and described by the two Sienese engineers. The machines continued to be reproduced in engravings as late as the mid-eighteenth century.