336, 



Cam bi'idff*;, , Philo^opliii;al^ ^9cieiy ■ , 



plane of mcidencc upon the pile. The latter \\m incliucd until 

 it depolarized the light, and then by means of the table of grarq 

 daation I found the ratios between the quantity of light polariaedj 

 and the total quantity; I obtained the following results :— ;-- hdi 



Angles of incidence 

 upon the dark 

 • glass. 



oooiio'ntlih t; 



Angles of incidence upon 

 tlie liilo when depolarization 

 ,' takes i>lace. 



. I /h ' li ' li 

 ^ iiocji; bili'f 



Hatios between the light poinded »ndj]^^j g 



^ . ■ total light. ■ „ . ° 



i jObicrved. 



cilptiU8«;?"l9ftib 



)-;liriH([-' 1! 

 I. g^(j( ='Trtf|flnuj;t9[4<3l~.!>i|i- 



-3q% :^ 'lo ooslius isr 

 Iqyoxgsf^aoubdKi Jon 



; S|nii sdi . 



Jaob 'Aftbaoubjiqaws^iaS.^ofh , £ si?. mMflfo lo ^aloiJujfJ^J^aub ar.l 



75 



uaqafa i' 

 tort of; 





'.Ilk in 



60oni{7 bn;i^"j 



o ^^. 3di n 



fodi;^'- 



OffJ 



raaTii ^ 



In order to calculate the ratios sought by the formula of 

 Fresnel, I have adopted for the superficial index of the dark 

 glass the number 1'4'25. According to the law of Brewster, this 

 number corresponds to an angle of polarization of 54° 56'. In 

 determining directly the angle of polarization of the glass, I 

 found it to be 54° 45'. - ' ^• 



,', I had commenced t'his"inVest'ig^6il'U''11HB\'^ta'.'6f'l{i^ 

 without knowipg that M. Arago had resiiincd' liis' researches iii 

 optics. I have since finished it, but would not ha\ e published 

 it today, ^ad,,»qj,,^I,j4^;^ft.Y!i%slyi,CQi}^Wt#. tP tl<?;,l»3:\b|^gn 



tion. 



y^ 



I loi noil-rmnn ^f (t ihiiiif nf tnliiU 'mU is "In ^miIbv "^ch yrf 



riliW bavigsffo t'13'fti ^loifw 'nb vnv oi T^hic; pi Ivjilqiilj/m ocl Jaum 

 baudi xUbS XLV. Frocdedihffs of Learned Societiestrr, aoiulubnaq 

 biiB ,i9j3nii>i.' fo't tr)8"I=:s\ 



yJ xiworia J?.i3 g^oatiuraedfromaiot.isa^tiuTptnft^O^ 9fl* moil 8'wollol 



Nov, TI, /^l^ the Matliematical exposition of soiine '©octrines o'^f 



1850. ^ Political Economy. By the Master of Trinity. Third 



Memoir. .,, 1 . ... _i ■■.,,■•.:. , ,,■; 



The object of thismenioir^vki'td'^mt oiit'scyme of thelaWs of'ifl- 

 ternational trade, taking into accouWt tlie effect of the import or 'ex- 

 port of money, i. e. of metallic cmTciicy. It was stated that when the 

 balance of imports and exports is deranged by the import of a new 

 commodity, previously produced at home, the effect is, to diminish 

 the annual import of gold and silver ; hence, to lower the scale of 

 pnce? in general ; hence, to increase the exports, and thus, to pro- 

 duce a new condition of equilibrium : and the necessary sup])osi- 

 tions being made, the amoute'bf 'depresMoia' in |^ieefe' arising from 

 such a cause was calculated. '' ;!>'"'•''■ "' V "'"' h't"' :;■,•: 



The Master of Trinity also made a communication relative to a 

 neiv kind of coloured fringes. He stated that he had, many years ago, 

 remarked that if we hold a candle before a diisly looking-glass at a 

 distance of six or eight feet, so that the image of the candle is near to 



