A study of high transverse energy events resulting from 400 GeV protons scattering from targets of hydrogen, carbon, aluminum, copper, tin, and lead has been performed with the E609 apparatus at Fermilab. Wire chambers and a highly segmented calorimeter detect secondary particles. The use of efficient jet collecting triggers and of a beam jet calorimeter have been originally applied to nuclear target studies in this thesis. A('(alpha)) scaling with hydrogen deviations is observed for E(,T) and planarity. The data provide evidence that A('(alpha)) scaling results from multiple scattering. Evidence for hadron jets is seen with a large solid angle calorimeter for all the targets when triggers requiring two high E(,T) single particles are employed. Jet cross-sections for nuclei are approximately determined herein. Jet event angular distributions possibly indicate that low and high transverse energy particles in jets from nuclei may result, in part, from different types of interactions.