Question: Given the following passage  "The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location.",  answer the following question. Note that the answer is present within the text.  Question: how were floods able to be forecast?
Answer:
a system of pulleys and wires to automatically calculate predicted tide levels