1579 -- 1644
Chemist, born in Brussels. Studied medicine, mysticism, and chemistry under the influence
of
Paracelsus. Dedicated many studies to gases—a term he coined. He was the first to use the
melting and boiling points of water as standards for temperature measurement. His experiments
mark the transition between alchemy and chemistry.
He was the first to conduct quantitative experiments on plant nutrition:
"I took an
earthenware pot filled with 200 lbs. of soil dried in an oven. I soaked this with
water and planted a willow shoot weighing 5 lbs. After 5 years the tree weighed 169 lbs. and
3 oz. The pot had been constantly wet only with rain or when necessary distilled water.
Finally, I again
dried the earth of the pot and it was found to be the same 200 lbs. minus
about 2 oz. Therefore, 164 lbs. of wood, bark and root had arisen from the water alone."
