Following a severe bout of malaria Thomas Spratt was given home sick-leave. As a result, he was able to spend the years 1848-49 studying the movements of the Bar sands at Teignmouth and published a book on the subject, dedicated to Sir William Reid, Governor of Malta. The book was entitled "An Investigation of the Movements of the Teignmouth Bar" and he gave all his data to the Teignmouth Harbour Commission. At this time the commission were struggling to relieve the local trade from an unjust tax, levied annually by the town of Exeter. Mr. Bell an assistant engineer on the South Devon Railway spent some months confirming the accuracy of Spratt's observations.