Radovi Pucića i Božidarevića iz hidromehanike i njezinih primjena ne spadaju u ona temeljna djela europske znanosti koja su postavila temelje toj grani znanosti. To nisu ni ona od manje važnih djela koja su utjecala na druge znanstvenike. Po svojoj prirodi to su teze koje su branili studenti na završnim ispitima, pa kao takve vjerojatno nisu morale biti izvorni znanstveni tekst. No, to pitanje o tezama koje su studenti branili nije definitivno riješeno u povijesti znanosti.The paper presents the theses on hydromechanics written by Nikola Lucijan Pucić (Nicolaus Lucianus de Pozza) and Ivan Božidarević (Joannes Bosdarius), published in Siena in 1791 and 1792 and defended at the Piarist Collegium Ptolemeum the same years. Pucić\u27s thesis is entitled Specimen physico-mathematicum (Physico-mathematical Specimen) and deals with problems in mechanics, hydromechanics, optics and astronomy.
In his thesis Theoremata ac problemata e scientia navali excerpta (Theorems and problems taken from the science of navigation), Božidarević limits himself to particular cases related to the application of hydromechanical laws to navigation. Both theses deal with basic laws of hydromechanics discovered before the writers\u27time (the pressure of liquids, the outflow of liquids from different vessels, the motion of liquids in pipes, the motion of solid bodies in liquids, etc.) and with their application. Pucić also used hydromechanical laws to determine the form of the Earth and discussed the theory of aerostatic balloons, an important issue at the time. Božidarević was more occupied with practical problems of navigation and tried to find theoretical explanations.
Thus, he explained how the wind moved sailing-ships, how and why a ship could be moved by means of oars, how the rudder was used to steer a ship and which laws of nature were applied in these cases
