278 



Mr. Lubbock on the Heat of Vapours 



Mr. Russell has calculated for me the following table, by means 

 of my expressions, and with the constants 



y = 1*5, £= - 1*192: 



No. 



Observed 



pressure 



P- 



Calculated 

 height in 

 miles. 



Temperature r. 



Density g. 



Calculated. 



Observed. 



Calculated. 



1 

 2 

 3 



0-76568 

 •5381 

 •5143 



0-000 

 1-895 

 2-131 



+30-75 

 14-74 

 12-68 



+30-75* 

 12-50 

 11-00 



•99999 

 •74276 

 •71514 



4 

 5 

 6 



•4968 

 •4905 

 •4666 



2-310 

 2-376 

 2-632 



11-10 

 10-52 



8-24 



.8-50 



10-50* 



1200 



•69473 

 •68736 

 •65928 



7 

 8 

 9 



•4626 



2-676 



7-85 



11-00 



•65457 



•4528 



2«785 



6-87 



8-75 



•64299 



10 

 11 

 12 



•4404 

 •4353 

 •4229 



2-926 

 2-985 

 3-130 



5-61 



4-99 

 3-67 



8-25 

 6-50 

 5-25 



•62828 

 •62222 

 •60744 



13 

 14 

 15 



•4141 

 •4114 



•3985 



3-236 

 3-269 

 3-428 



2-80 

 2-61 

 1-05 



100 

 4-25 



2-50 



•59692 

 •59346 



•57818 



16 

 17 



18 



•3918 

 •3901 

 •3717 



3'512 

 3-533 

 3-772 



0-28 

 + 0-08 

 - 212 



0-00 

 + 0-50 

 - 3-00 



•57010 

 •56805 

 •54576 



19 

 20 

 21 

 22 



•3696 

 •3670 

 •3339 



•3288 



3-800 

 3-835 

 4-295 

 4-369 



- 2-37 



- 2-70 



- 7-00 



- 7-70 



- 1-50 



- 3-25 



- 7-00* 



- 9-50 



•54321 

 •54004 

 •49947 

 •49317 



The observations marked with an asterisk are those which were 

 employed in deducing the constants. 



The temperatures calculated by Mr. Russell from my formula 

 may be considered as identical with the " temperature regularised 

 par la continuite", given by M. Biot in the Conn, des Te?nps 9 1841, 

 p. 13. The observations* of M. Gay Lussac of temperature are re- 

 presented in the following diagram: 



* The irregularities of the observations of temperature in any future ascent might 

 perhaps be diminished if the ballast were suffered to escape gradually in a continued 

 stream. 



