Source: The Alchemy Web Site
Alchemy is a multifaceted subject. It is an early form of chemical technology exploring the nature of substances. It is also a philosophy of the cosmos and of mankind's place in the scheme of things. Alchemy developed an amazing language of emblematic symbolism which it used to explore the world. It had a strong philosophical basis, and many alchemists incorporated religious metaphor and spiritual matters into their alchemical ideas.
About four thousand printed books were issued from the 16th through to the late 18th centuries, exploring alchemy from a multiplicity of different perspectives. Many thousands of manuscripts, hand written works, letters, notes and commentaries exist in the libraries of Europe and North America, some beautifully illustrated with coloured images. Alchemy was thus, through the sheer volume of writings, influential throughout the early modern period. Its influence can often be seen in the work of writers, poets, and artists of the time.
In the 20th century, interest in alchemy was revived, following its decline and total eclipse in the 19th century. Today alchemy is often used as a catch word for obscure and enigmatic symbolism, or for the idea of spiritual transformation and inner change.