ENGELMANN—ELEVATION OF ST. LOUIS. 665 
than my standard, E. 1., when I sent it, and 0.070 lower after 
it was returned, so that the mean difference was assumed to 
have been 0.075 inches. Dr. Barton found his instrument, B., 
on an average 0.045 inches lower than E. 2., which would 
give its rate at 0.120 inches below E. 1. 
The 282 corresponding observations at New Orleans and 
St. Louis, extending over a time of more than four months, 
give the following average results after correction for the dif- 
ference of rate: 
New Orleans. St Louis. 
Barometer, 30.125 29.584 Eng. inches. : 
Attach. Therm. 66.88 53.01 degrees Fahrenheit. 
Open air Therm. 59.09 40.80 . 4 
These results converted into metrical measure for the ap- 
plication of the tables of Delcros, as published by the Smith- 
sonian Institution, give 
New Orleans. St. Louis. 
Barometer, h—=765.17; A'=751.42 millimetres. _ 
Attach. Therm. T= 17.16; T’= 11.68 degrees Centigr. 
Open air Therm. t= 15.06; t= 489 “ a 
: Metres. 
Table I. gi Se ot he oo 
3 etiide h' = 8060.1 
144.4 
Approximate elevation of E. over B 
Table IL., correction for temperature of Barom. stot SEE od 
137.3 
Correction for temperature of air: 
15.06 X4.89=19.95 x grag 
39.80 137.8 divided by 1,000= Sear : 
Table ITT. Latitudes 38° 30’ and 30°; mean 34° 15'5 
correction - “ . pi hee 0.35 
Table IV., correction for decrease of gravitation =~ 
- 143.26 
Corrected elevation of E. over B. - - ; 
8 
Enoelmann’ : tion over Barton 
gages fom i yam “a 143.26 metres, or 469.8 Eng. ft. 
station 4 
B. above Gulf, according to Dr. Barton's state- gi 
ment, ee he ‘<é ae - - ak 
E. above Gulf. - - at et “ 
E. above City Directrix a ae ies : 
age aa 
City Directrix above Gulf - - ~* 
stitution, some time ago, to obtain the aid of natin version Sod or 
ments for the distribution of correctly rated standot” ai, will be ied 
ey thly and yearly publications of the results obtained, carr 
