Ariwara took up a pastime then fashionable amongst the nobility. Seawater was boiled down in salt kettles (塩竃 'shiogama')...the purpose not to produce salt, but rather to admire the different colours of smoke created in the process.
Jūrin-ji has recreated Ariwara's shiogama.
Some believe that Ariwara used his salt kettle to create a primitive form of smoke signal, indicating to Takaiko (when she was at staying at Ōharano-jinja) that he loved her still.