Such 'bubbly water' refers to the soda water, or carbonic water perhaps, can expands the blood vessels and lowers the blood pressure.
The laconium therapeutic stone is for people who feel the Finnish Sauna is too hot or for those who feel that the humidity of the traditional steam bath is too high. The purifaction process starts in a harmonious atmosphere with approximately 50C to 60C. This gentle tratment is enjoyable for all. The most famous bath from the antique times was called by the Romans "Tepidarium". This was knows as the "artificial fever" with a cabin temperature of about 39C. this temperature creates an optimal condition to build the immune system.
Is totally soluble in water, and diffuses in generous quantities when the diluted solution is poured onto the hot stones of the stove (10 to 20 ml diluted in a litre of water). Enjoy the fragrances as they spread generously around the room. Never use pure essential oils in sauna!