Taken from an excellent book by Alistair Moffat & George Rosie called " Tyneside - a history of Newcastle & Gateshead from Earliest times " - ISBN 1-845596 013 0

" Tynesiders made good use of their mineral riches . Coal is one of the best sources of heat and energy known to us and where there is coal , there is often brine-rich water . When this is left to evaporate in the Sun or heated in shallow pans , it leaves deposits of salt , yet another valuable commodity . So valuable , in fact , that people were once paid wages in salt . The word " salary " derives from the the Latin word "salarium" , which is how Rome occasionally paid its troops . By the beginning of the 18th century , there where more than 170 salt pans operating on Tyneside , most of them in North and South Shields at the mouth of the river ( some street names were derived from the industry , just off Commercial Road is a small road named "Pan Bank" and off that there was a "Pan Yard " - author ) The Tyneside salt industry was an intriguing one . Most of the raw material , the brine water , came from local mines . The so called Salt pans in which the brinewater was cooked were long , shallow vessels , usually between 21/2 ft to 3ft deep , made from cast-iron boiler plate riveted together with angle irons and set up over brickwork flues . The dimensions varied from 25ft by 20ft to 135ft by 30ft . The smaller ones were heated at 107c to produce fine grained salt for domestic use . The biggest of the pans were heated at 40-50c and produced rougher "bay" salt . In between , there was a grade known as fishery salt which , as its name suggests , was used for salting fish at sea . It was a simple but effective chemical process and it lasted in various parts of Britain ( such as Prestonpans on the Firth of Forth ) until huge seams of underground rock salt were found in places like Cheshire , Barrow in Furness , Droitwich and Carrickfergus , in Northern Ireland . By the end of the 19th century , rock salt had swamped the British market and Tynesides salt pans had more or less ceased to exist . "