FOOTNOTES:
Reading edition
Transcriber's Note: The following corrections have been made to the original text.
Page 4: "Terrestial distances" changed to "Terrestrial distances"
Page 9: "we must chose," changed to "we must choose,"
Page 12: "acromasie" changed to "achromatism"
Page 15: "inparticular" changed to "in particular"
"supposing, that" changed to "supposing that"
Page 16: "393.4 mm" changed to "393.4 μμ"
Page 20: "for which stars if" changed to "for which stars it"
Page 22: "sphaerical" changed to "spherical"
Page 23: "principal scource" changed to "principal source"
Page 25: "lense with 15 cm" changed to "lens with 15 cm"
Page 27: "Through the spectroscopie method" changed to "Through the spectroscopic method"
"made to its principal" changed to "made its principal"
"american manner" changed to "American manner"
Page 35: "many tenths of a year" changed to "many tens of years"
Page 38: "same appearence" changed to "same appearance"
Page 47: "red stears" changed to "red stars"
"dispersion in M" changed to "dispersion in M"
Page 49: "smaller the" changed to "smaller than"