diff --git a/lib/xmet/sounding.py b/lib/xmet/sounding.py
index 23e972c..ce63863 100644
--- a/lib/xmet/sounding.py
+++ b/lib/xmet/sounding.py
@@ -10,9 +10,7 @@ from xmet.series import Series, SeriesIntersection
 from xmet.thermo import follow_dry_adiabat, \
                         follow_moist_adiabat, \
                         follow_saturated_mixing_ratio, \
-                        pressure_height, \
-                        kelvin, \
-                        celsius
+                        kelvin
 
 LAPSE_RATE_DRY   = 9.8 # degrees C per 1000m
 LAPSE_RATE_MOIST = 4.0