The link is to a PDF which is itself an abridged version of David White's history of alchemy.
As edited by thehealingproject.net, it's a good read. Here is a brief excerpt:
The concrete emphasis of the alchemical quest is emphasized repeatedly: Liberation [arises] from gnosis (jnana), gnosis [arises] from the maintenance of the vital breaths. Therefore, where there is stability, mercury is empowered and the body is stabilized. Through the use of mercury one rapidly obtains a body that is unaging and immortal, and concentration of the mind. He who eats calcinated mercury (mrtasutaka) truly obtains both transcendent and mundane knowledge, and his mantras are effective.
Supernatural powers and bodily immortality, the goals of the tantric practitioner, cannot, however, be realized through alchemy alone. The absolute, Siva, too plays an active role in alchemical transformation: "So long, however, as Siva does not descend to block the impurity that impedes the soul's liberation, and so long as one's fetters to this world remain uncut, there is no way that true discrimination can arise through the use of calcinated mercury." Divine grace implies its human complement of devotion (bhakti), which is also present in the alchemical synthesis, even if such is unusual to tantrism, which places a greater emphasis on ritualized forms of worship (puja, upasana) than it does upon devotionalism. p 174
8. Homologous Structures of the Alchemical Body
The kundalini in the body of the yogin is an incarnation of the feminine in this tradition and thereby incarnates all the perils and joys that women can represent for men. She is divine energy (sakti) and female materiality (prakrti), but she is also a tigress who can drain a man of all his energy and seed. She is twofold, and it is in this perspective that yogic sources speak of this internal female serpent by another name: she is bhogavati, a term that at once bespeaks her enjoyment (bhoga, from bhuj, "partake, enjoy"), her coiled form (bhoga from bhuj, "coil, curl"), and her female sex (-vati is a feminine ending). As bhogavati, she is the serpentine female principle with the subtle body.
There are some paragraphs about tantra which I may post in that group later.