1917] KRAYBILL—ALKALI SALTS 43 
dependent primarily upon the content of potassium combined with 
organic acids. 
NESSLER (12) concluded that potassium sulphate exerts a 
favorable influence upon the burn; while Jenxrns (6) found that 
fertilizing with potassium sulphate increased the content of sul- 
phuric acid in the tobacco so that in some cases it injured the 
burn. GARNER (4) concluded that sulphates in general are inju- 
rious to the burning qualities, but not to so great an extent when 
all of the sulphuric acid is combined with the potash; while 
PATTERSON (14) found no apparent relation of the content of sul- 
phuric acid to the burn. 
NESSLER (12, 13), KISSLING (7), BEHRENS (2), VAN ocuke. 
(17), BarTH (1), PATTERSON (14), CARPENTER (3), NER 
(4) agree that chlorides are injurious to the burn. Kussiine (8) 
considered the content of ash to have little influence upon the 
burning qualities; while Patrerson (14) and CARPENTER (3) 
concluded that a high content of ash was conducive to a good burn. 
NESSLER (12) found that calcium and magnesium have little effect 
except to whiten the ash. Kusstinc (7) found good burning eo 
samples of tobacco high in content of calcium and fairly high in 
magnesium. GARNER (4) concluded that calcium in general does 
not greatly affect the fire-holding capacity, but is essential in the 
production of a good ash, and that large amounts of magnesium a 
injure the burn. Barta @) treated several kinds of paper with . 
phosphate is injurious > 
to the en  Gaunns (4) found di-potassium phosphate neutral - 
in its effects upon the burn. = 
sk consideration of the reason, for the aE in of 
: the potassium salts of organic acids has led to several theories. oe 
: SCHLOSING (15) attributes their favorable action to the fact t that os 
: and y Se $ mass. soa ee (2) 
