What is maritime history and why is it important to us today? How did changes in technology affect communities in San Francisco and California in the early 1900s? Objective Students will analyze primary sources to explain HERCULES' role as a tugboat. Preparation 1. Print photos for gallery walk and place around the classroom. 2. Provide students with post-it notes. 3. Print worksheets. Materials Slides to guide the investigation of Hercules through primary and secondary sources. Download What is Hercules - Classroom Slides Photos and articles to print out for gallery walk activity and referenc Duration: 60 Minutes.