the late Dr. Joule's Thermometers. 



499 



and from this we may calculate for the temperatures lyiug 

 between 14° and 22° the difference between the Tonnelot 

 and Joule readings. These are entered in Column II. of 

 Table VIII. ; the remaining columns have the same meaning 

 as those in Table VII. 



Table VII. 



I. 



J-rrt, 



7-828 

 9-375 

 12-293 

 12-534 

 13-127 

 13-310 

 13-324 

 13-737 

 14-186 

 15-416 

 15843 

 18-291 

 18-577 

 18-699 

 18-777 

 21-145 

 23-954 

 24-761 

 30-894 



II. 



T T -T 7 , 



-•001 

 + •009 

 •010 

 •014 

 •015 

 •024 

 •015 

 •031 

 •016 

 014 

 •024 

 •039 

 •020 

 •032 

 •036 

 •013 

 •010 

 •006 

 •013 



III. 

 T N — T T . 



•037 

 •043 

 •054 

 •055 

 •056 

 •057 

 •057 

 •058 

 •059 

 •063 

 •064 

 •069 

 •072 

 •072 

 •070 

 •077 

 •083 

 •084 

 •092 



IV. 



•038 

 •034 

 •044 

 ■041 

 •041 

 •033 

 •042 

 •027 

 •043 

 •049 

 •040 

 •030 

 052 

 •040 

 •064 

 •064 

 •073 

 •078 

 •079 



V. 



(V t *)e. 



•052 



•058 

 •077 

 •079 

 ■080 

 •083 

 •083 

 ■085 

 •085 

 •094 

 •094 

 •104 

 •104 

 •104 

 •104 

 •108 

 •112 

 •116 



VI. 



s. 



•014 

 •024 

 •033 

 •038 

 •039 

 •050 

 •041 

 •058 

 •042 

 •045 

 054 

 •074 

 •052 

 •064 

 •040 

 044 

 •045 

 •038 



Table VIII. 



I. 



II. 



III. 



IV. 



V. 



VI. 



T T . 



T T~ T r 



T N" — T T- 



T i" T *- 



(V t *)r- 



8. 



o 



12 



+ •0171 



-•053 



•036 



•077 



•041 



14 



•0170 



-•059 



•042 



•085 



•043 



16 



•0169 



-•065 



•048 



•094 



•046 



18 



•0168 



-•070 



•054 



•101 



•047 



20 



•0167 



-•075 



•058 



•109 



■051 



22 



•0166 



-•079 



•062 



•110 



•048 



The two series of measurements agree in showing a differ- 

 ence of nearly o, 05, which must be either due to a real 

 difference between Rowland's " perfect " air-thermometer and 

 that of Chappuis, or to some error in one or other of the 

 comparisons. 



We have no information at all as to how Joule proceeded 

 in comparing together his thermometer with that of Rowland. 

 The numbers furnished by Joule are obviously not those 



