THE m A L m r s OF :I'URPES'I'ISI.: airs. IIT F. \V. ~I C I i , \ I l D S O S ASI) J. I,EOS.\III) IIO!VES.
Light 1iytlroccirl)ons n p p r to be iilniost tlic sole Pine oils iidiiltcrniits used for coniiiicrcinl tiirlieiitiiies.
iise tlicir prescncc iii tiirpeiit iiie is objcctioiiiible. iis tlicy net iiiore powerfully oii tlie skin niid cnwc coiisidcriiblc iiifliiiiinintioii. A s 'illelitti litis stilted, iiicrc sliciking of tlic oil with liiilf its voliiinc of n soliitioii of (i Iwr cent. of iotliiio in cnrboii tctriichloride niitl siibseqiient liciitiiig in i i \vntcr biith for one iiiiiiiitc will givc 11 dnrk grccii coloiir if piiioliiis iirc 1)rcsciit.
~'o/ttrit/ietry.-Oii tic'coiiiit of the prcscnce of varying 'niiioiiiits of liuvo niitl tlextro-rotcitory Iiiiicncs iii piire tnrpeiitines, polnriiiictric iiictlioda nre of very littlc service.
Refroctirc i)tdez.-\'c fiiid tliiit the Al)lii. refrnctonictcr n i i d , sitliiii ii ccrtniri riiiige, Zciss's I~iityrorcfriictoiiictcr givc invnliinblc-aid in tlie niiiilysis of tiirpciitiiics. Pure tiirl'ciitincs froiii vririoiis soiirces give rcfriictirc iiidiccs of 1470 to 1.474 lit IS,' C'., wliilc 1iyclrociirl)oii atliiltcrciiits yicltl tigiircs vcirviiig iroiii 1.41 to I-IO lit 1510 C. Specific grtrchy.-Wic slwcilic griivity iiiriiisIies tin iiitlicntioii iiliiiost. its vnliiiible iis tlic refriictivc iiidex ; but it is iiot (is ciisily iipplicnlh to very siiiiill aiiioiiiits of liqiiicl. Speci/ir re/rfir/i~ii/y.-'I'licre is no spccial ndvantcigc in iisiiig tlic Loreiitz tiiitl Loreiiz foriiiiilii -.,----ovcr tliiit of Gladstonc iuid Dale, --, for the spccific ref activity fnctor. (ir=rcfriictire iiidcx ciiid d=sp. grcivity.) Coriipurcd with tiirpciitiiic tlic liglitcr Iiydrociirboris slio\v both lower dcnsitiea nnd refrnctivities, 011 this iiccount tlic clivisioii of thu hitter IJY tlic forincr diiiiiiiislies the tlilicrciice bctwecii the specilic refriictiritics of tlicsc two cliissea of botlics : liciicc we do not liiid the sl'ccilic rrfriictivitica of service in the iiiialysis of coinincrciul t iirlwiitiiics, tl2 -1 01-f 2 ) d 11-1 d \'c obtaiii :-\Ye Iinrc bcloi~c iia two ntliiltcrciiitn, A nntl ', tiiitl iiiistiircs of tlicsc with 11 p r c tiirpciitiiic :-of Aiiicricciii '* Diiyliglit Iwtroleiiin '' :-