"Theory and Practice of Fortifications" by Captain Cristobal de Rojas, 16th Century

Captain Cristobal de Rojas (1555-1614) was born in Toledo, Spain, and is considered one of the most significant militar architect and engineer, due to the large amount of treatises he wrote about this matter during 16th Century. He specialized on fortifications for defense against pirates and corsairs, after the looting of Santander by "Sir" Francis Drake. His talent was soon detected by his commander, and initiated a long trip to inspect fortifications of Gibraltar, Ceuta, Tarifa, Lisboa, Cadiz... was after the inspection of Cadiz fortification when he made several recommendations that were not considered by the Spanish Royal Navy, even when he insisted passionately to militar authorities and the King. Only three years later this important city was almost destroyed by British Admiral Howard. After that, his talent was recognized by the King Felipe III, and started a military career in which he travelled around the world planning deffenses and fortifications for the Spanish imperium.

The most important treatise of Captain Cristobal De Rojas is “Theory and Practice of Fortifications”, printed in 1598 in Madrid, with Royal Privileges.

Bombs and Explosives handbook

I found this handbook of bombs and explosives -17th Century- in the Bavarian State Library during my travels through open virtual libraries around the world. But my investigation about author (Hans G Schirvatt?) concluded with a poor-to-nothing result. The only reference I could find is that all weapons shown in this handbook were used during 17th century first quarter European wars, and were contemporaneous to Flandes war –also known as eighty years war or Netherlands independence war from Spain-.

Was during this war when the use of bombs with temporizers reached an incredible level of perfection, because some episodes –especially for city sieges like Breda- were based on “underground techniques”: an special task force of military engineers dig tunnels to approach enemy troops, put the bombs and grenades with combustion or mechanical based temporizers and escape using the same tunnel, with time enough –sometimes not- to avoid explosion. An authentic massive destruction weapon manual in 17th Century.

Some episodes of the eighty years war here.