leaves were produced. At this time in tea's history, the nature of the beverage and style of tea preparation were quite different from the way westerners consume it today. Tea leaves were processed into compressed cakes form. The dried teacake, generally called brick tea was ground in a stone mortar. Hot water was added to the powdered teacake, or the powdered teacake was boiled in earthenware kettles then consumed as a hot beverage. See matcha for the Japanese version of using powdered green tea, which is derived from older Chinese customs. A form of compressed tea referred to as white tea was being produced as far back as the Tang dynasty (618–907 CE). This special white tea of Tang was picked in early spring, when the tea bushes had abundant growths which resembled silver needles. These "first flushes" were used as the raw material to make the compressed tea. Tea is an important item in Chinese culture and is mentioned in the Seven necessities of (Chinese) daily life. Tea was also used as a relaxing therapy for the Chinese. In 1753, Linnaeus described the plant as a single species, Thea sinensis. Later, however, he recognized two species, Thea Bohea and Thea viridis, as cultivated in China, and it was long thought that these were the origin of black and green tea respectively. Roasting and brewing Steaming tea leaves was the primary process used for centuries in the preparation of tea. After the transition from compressed tea, the production of tea for trade and distribution changed once again. The Chinese learned to process tea in a different way in the mid-13th century. Back in the Tang Dynasty, tea was commonly prepared by bringing water to a boil and taking a cup of water out from the pot. Afterwards, the water would be stirred and tea powder would be poured into the swirling water. Finally, the water which was scooped out earlier was then poured back in which prevented the tea from over-boiling. Fermentation After cutting, tea is subjected to a so-called "fermentation." This process is not actually a fermentation, which is an anaerobic process, but rather an enzymatic oxidization of the polyphenols in the tea leaves, yielding theaflavins and thearubigins. When the tea leaves are dry, fermentation stops, allowing some control of the process by manipulation of the drying rate or adding water after drying. Fermentation can also be interrupted by