This photograph was taken by Capt. Rollo Beck in 1905. It is of a triple effect vacuum evaporator manufactured by McOnie Harvey & Co., Ltd., Glasgow. Sugar was concentrated by passing cane liquor through three vessels, each with an increasingly higher vacuum and lower temperature in order to achieve evaporation. Not only did the evaporator reduce the amount of required fuel through steam re-circulation and evaporation at lower temperatures, but it also protected the sugar product from destruction at higher temperatures.
