change Institute for Civil Service to: Ipasgo, the health care authority for the state

change about a mile to: about one-third of a mile

change a medical clinic to: a public health clinic

change the hospital physician to: a doctor at the clinic

copernicium-285 should be: copernicium-277

change chain to: chains

change 137,893 to: 88,996

line 25, delete “salts” so reads: …some ores containing uranium and thorium…

line 27, delete “salts”

line 29, change uranium salts to: uranium ores

change: Also in 1900… to: In 1912

change astatine to: astatine-213