276 



Prof. E. J. Mills and J. Hogarth. [Jan. 23, 



Table II. 



Number. 





Equation. 





Probable error. 



1 



y =13 



yooz — 



4o54oa + 



•014330a 2 





0ol5 



2 



y = U 





• K £A1 A™ 1 



ooy iy^4- 



•017755a 2 





04zd 



3 .... 



y=lS 



0Zo4 — 



4y4/oa + 



•014629a 2 , 





• AQOO 



03zd 



4 



2, =15 



41 (J (J — 



• £077 1 

 OZY /5a 4- 



•021712a 2 





Oolo 



5 



y=U 



OJ oo — 



4yoooa4- 



•013833a 2 . 





• A1 7Q 

 Ul id 



6 



y=U 





• •71 707™ 1 



•026959a 2 . 





• A K 1 A 



0519 



7 . . .. 



y = U 



• 1 KO*7 



15d7 — 



o0oo5a + 



•019943a 2 . 





0zo9 



8 



y=U 



1004 — 



54zyoa4- 



•016387a 2 







9 



y = 15 



o/y^-=- 



• tCQAA^™ L 



5oU(J0a4- 



•017402a* . 





• AO 



10 



y = U 



54oU — 



• K IX 7 7A™ 1 



5o/70a4- 



•018459a 2 . 





■ AOOO 



11 .... 



y = U 



ol54 — 



• KROA A™ 1 



5oZ4Ua 4- 



•018388a 3 . 





Oooo 



12 



y = 15 



0/4/ — 



ooooUa4- 



•023514a 2 





• AQsJA 



13 



y = 18 



• Ol A O 



Z14Z — 



00^0405 



•020109a 2 . 







14 



y = 16 



■6262- 



•65155a 4- 



•020546a 2 . 





•0313 



±0 .... 



77 — "1 7 



•2230- 



•64521a 4- 







•0227 



16 .... 



2/=14 



•6339- 



•48232a + 



•013474a 2 . 





•0177 



17 .... 



y = lo 



•5954- 



•56252a + 



•017796a 2 . 





•0401 



18 .... 



y = 16 



•4546- 



■65417a 4- 



•022141a 2 





•0455 



19 .... 



y = l7 



•5923- 



•58714a 4- 



•016131a 2 





•0088 



20 .... 



y=U 



•9011- 



•45421a? + 



•012057a 2 . 





•0255 



By the aid 



of these equations we can now calculate 



the initial 



specific rotation of lactin, or the rotation when a = calculated to unit i)f 

 weight. When a=0, y = a', and the permanent rotation being known, 



a x 59 *17 



the initial specific rotation = . — . The following are 



permanent rotation 



the values found, the chloride experiments being averaged by them- 

 selves. 



Average of Nos. 1, 2, 3, 10, 11, 12, 



» Nos. 4, 5, 6 



„ Nos. 7, 8, 9 



„ Nos. 13, 14, 15 



„ Nos. 16, 17, 18 



Single experiment, ISTo. 19 



•98 

 •90 

 •97 

 •87 

 •37 

 •30 

 •16 



.... 93 



.... 91 



.... 91 



.... 91 



.... 91 



.... 95 



No. 20 92 



Average of the twenty experiments, 92 0, 63. 



On differentiating the equations, putting ^=0, and calculating the 



(XX 



values of x and y, we find that the values of y thus got do not corre- 

 spond to the permanent rotation, but are always greater; showing 

 that the change in rotatory power does not progress according to the 



