Handbook of the polariscope and its pracitcal applications / adapted from the German editon of H. Landolt, by D.C. Robb and V.H. Veley.

  • Hans Heinrich Landolt
Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: Handbook of the polariscope and its pracitcal applications / adapted from the German editon of H. Landolt, by D.C. Robb and V.H. Veley. Source: Wellcome Collection.

    42/320 (page 22)
    ACTIVE. INACTIVE. 1 Dextro-rotatory. Lee vo- rotatory. By. Combination of equivalent Molecules of right and left-handed Modifications. By Difference in the Atomic Structure of the Molecule. Dextro-tartaric Acid Lsevo-tartaric Acid Para-tartaric Acid Meso-tartaric Acid Malic Acid from Dextro - tartaric Acid1 Natural Malic Acid j Malic Acid from I Para-tartaric Acid1 Malic Acid from Succinic Acid Laurel or ordinary Camphor Matricaria Camphor Bacemoid [or Para] j Camphor2 — Camphoric Acid from Laurel Camphor Camphoric Acid from Matricaria Camphor Para - camphoric | Acid from Para Camphor or La- ! vender Camphor Meso - camphoric Acid3 Similar conditions are found to exist in other substances, with the difference that the two oppositely active isomers exhibit unequal rotatory powers. Thus, the following occur in dextro-rotatory ( + ), lsevo-rotatory ( —), and inactive (0) forms:—glucose (as dextrose +, lsevulose —, and glucose obtained by heating cane-sugar with water to a tempera- ture of 160° Cent., 0) ; terpenes (australene, the English oil of turpen- tine +, terebenthene, the French oil-, terebene 0); amyl-alcohol (that formed from the laevo-alcohol by conversion into the chloride and reconversion into alcohol +, fermentation-amyl-alcohol and the modification obtainable from either by distillation with caustic potash 0). See Le Bel4 ; Balbiano.6 _ . In many substances one of the two active modmcations is un- known. For example: ethylidene-lactic acid (from musclejnice +, by fermentation or synthesis 0); cymol (from oil of Roman cumin +, 1 Bremer: Ber. d. deutsch. chem. Gesell. 1875, 1594. 3 Chautard: Comptes Bend., 38, 166 ; 56, 698. Erdmann : J our n. fur prakt. Chem. 9°’chlutard: Jahresb. fur Chem. 1863, 394; Jungfleisch: Jahresb. fur Chem. 1873, 631. Wreden: Liebig's Ann. 167,302. i Le Bel: Bull. soc. chrn. [2] 25, 545. 5 Balbiano : AW. fur Chem. 1876, 348.