Books behind pictures

The “Nouveau dictionnaire encyclopédique universel illustré“, to call it by its full and original name, was published in Paris between 1886 and 1891, under the direction of Jules Trousset. It is said to be complete in six volumes, although a seventh one was released later as an update. The sixth volume is made of maps and charts. These books are in quarto format, approximately 25×35 cm and contain some 800 pages each, except for the smaller sixth one.
Typically following the eighteenth century humanist tradition, which saw the edition of the encyclopedia by Diderot and d’Alembert, it combines lexicographical endeavour with extended information on technical subjects. A particular emphasis was placed on chemistry and electricity, which were at the time fields of recent discoveries, as well as on legal matters. It holds numerous illustrations (over 3000), most of which are skillfully executed, even though the printing leaves something to be desired. Wood engraving was at the time a popular reproduction technique, used in mass publication. As in many books made in the late nineteenth century, the paper has turned yellowish and become very fragile, due to acidity, but it hardly shows any brownish stains.
Most of it is available on Gallica, the site of the french national library, as a series of six files which can be downloaded either in the pdf or in the tiff format. These files are in image mode, not text and over 100 MB each. At this time, the second volume is missing.
Finally, I have to say that its interest nowadays is mainly historical; if you are looking for accurate, up to date information, you’ll probably be better off searching Wikipedia…