ARCHAEOLOGICAL CHEMISTRY—EXPLORING HISTORY WITH CHEMISTRY - Chemistry: Notable Research and Discoveries - page 191

CHronology

1 c . e . American statesman and scientist Thomas Jeffer-

son (1743-1826) directs one of the earliest archae-
ological investigations—an excavation of a Native
American mound in Virginia. This and other early
excavations help to establish the scientific methods
of archaeology.

190 Russian scientist Mikhail Tswett (1872-1919) pub-

lishes the first description of chromatography.

191

American chemist Theodore Richards (1868-1928)
discovers lead of varying mass (due to different
isotopes).

British chemist Frederick Soddy (1877-1956) de-
velops the concept of isotopes.

1919 Building upon the work of others, British scien-

tist Francis Aston (1877-1945) develops the mass
spectrometer.

19 British archaeologist Howard Carter (1874-1939)

leads the exploration of Egyptian pharaoh Tut-
ankhamen's tomb.

199 University of Chicago chemist Willard Libby (1908-

80) develops the technique of radiocarbon dating.

190s British scientist Francis Crick (1916-2004), South

African biologist Sidney Brenner (1927- ), and
other researchers establish the genetic code by
which the sequence of DNA can be understood.
The development of advanced sequencing tech-
niques, as used in many branches of biology as well
as archaeological chemistry, followed.