GENERAL INDEX. xix 



PAGE 



Table XVI. Height, in English Feet of a column of air corresponding- to a 



Tenth of an Inch in the Barometer ..... 427 



" XVII. Height, in French Feet of a column of air corresponding to a 



Paris Line in the Barometer ...... 427 



• XVIII. Height, in Metres of a column of air corresponding to a Milli- 

 metre in the Barometer ....... 427 



" XIX. Height, in Metres of a column of air corresponding to a Milli- 

 metre in the Barometer at different Temperatures and Eleva- 

 tions ........... 42!:t 



" XIX'. Height, in English Feet of a column of air corresponding to a 

 tenth of an inch in the Barometer, at different Temperatures 

 and Elevations ......... 430 



" XX. Correction to be applied to the means of the Hours of Observa- 

 tion to obtain tiie True Mean Barometrical Pressure, Phila- 

 delphia .......... 431 



" XXI. Correction to be applied to the means of the Hours of Obsei-va- 

 tion to obtain the True Mean Barometrical Pressure, Green- 

 wich 4.12 



" XXII. For reducing Minutes into Decimals of an Hour . . . 433 



'• XXIII. Correction for curvature and refraction ..... 434 



Thermometrical Measurement of Heights. 



'• XXIV. Regnault's Barometric Pressures corresponding to the Tempera- 

 ture of Boiling Water ....... 438 



'• XXV. Regnault's Barometric Pressures corresponding to the Tempera- 

 ture of Boiling Water, revised by Moritz, in metrical mea- 

 sures 442 



*' XXVI. Regnault's Barometric Pressures corresponding to the Tempera- 

 ture of Boiling Water, revised by Moritz, in English measures 444 



V. GEOGRAPHICAL MEASURES 447 



a.) Comparison of the measures of Length most generally used for indicating 



altitudes 449 



Table I. Conversion of French Toises into ^Metres .... 4B0 



" II. Conversion of French Toises into Paris Feet .... 460 



" III. Conversion of French Toises into English Feet . . . 461 



" IV. Conversion of French Toises into Rhine Feet . . . 461 



" V. Conversion of Metres into Toises ...... 462 



" VI. Conversion of Metres into Paris Feet ..... 463 



" VII. Conversion of Metres into English Feet .... 466 



VIII. Conversion of Metres into Rhine, or Prussian Feet . . 474 



* IX. Conversion of Metres into Feet of Vienna .... 474 



* X. Conversion of Paris Feet into Toises ..... 47.'> 



