SALT MANUFACTURE IN HONG KONG
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of the soil is usually done in the evening and sprinkling with sea-water over the soil in the next morning. These processes are repeated for three to five days depending on the weather and the season. When enough salt is believed to have accumulated in the loosened soil after repeated sprinkling and evaporation of the sea-water, the soil is collected into piles and carried to the vat by coolies hired by the salt-farmer of the saline.
Figure 2. A harrow employed for loosening the soil.
The leaching vat (figure 1, and figure 3) is an elongated hollow erection of earth about 50 to 80 feet long, 5 to 8 feet wide and 4 to 5 feet high. A narrow longitudinal canal is dug in the bottom of the vat and over this coarse twigs and dry grass are laid to serve as a sieve to prevent collapse of the prepared soil during leaching, figure 3, G and T. When all the prepared salty soil has been heaped up in the hollow space of the vat it is pounded with a very heavy wooden hammer into a mass of soil as compact as possible, figure 3, PSS. Having completed the task of compacting the prepared soil in the vat, sea-water is conveyed from the reservoir-pond behind to cover and to leach it slowly overnight in order to extract the salt.