Why did inventors need physical demonstrations?

Would a vertical pipe be enough to test the hydrostatic device by itself?

The response stresses the need to demonstrate actual operation, alongside theoretical study, in an era before computer simulation.

A viewer asks whether a hydrostatic device alone could be tested in a vertical pipe. The response distinguishes testing an idea in theory from demonstrating its actual operation. An inventor seeking official backing often had to build and test a working mechanism because modern simulations and digital models were unavailable. Physical trials supplied evidence that an institution could inspect. The private workshop provided room to turn the proposal into a demonstration.