July 1,1925 Spreaders and Spreading Qualities of Spray Materials 7 5 
Table II .—The spreading properties of various substances on fruit-tree leaves and 
apple fruit 
Substance 
Concen¬ 
tration 
Apple 
leaves 
Pear 
leaves 
Prune 
leaves 
Apple 
fruit 
Sodium palmitate _ 
Per cent 
1.0 
Good_ 
Good_ 
Good.— 
Good. 
Do____ 
.1 
Medium __ 
Poor_ 
Poor_ 
Medium. 
Do_ __ 
.01 
None_ 
None_ 
None_ 
None. 
Sodium stearate. ____ 
1.0 
Good_ 
Good_ 
Good_ 
Good. 
Do ... 
. l 
Medium 
Poor _ _ 
Poor__ 
Medium. 
Do ... 
.01 
None_ 
None__ 
None__ 
None. 
Sodium oleate- 
1.0 
Poor.. 
___do_ 
Poor__ 
Poor. 
Do. 
. l 
None.-_ 
__do_ 
None. _ _ 
None. 
Do__ 
.01 
_do_ _ 
___do_ 
_ _do.. 
Do. 
Potassium oleate ... 
1.0 
Poor__ 
___do_ 
Poor_ 
Poor. 
Do.. . 
A 
.01 
None __ 
..do_ 
None_ 
None. 
Do_ 
___do.. 
___do- 
___do.. 
Do. 
Soap, Ivory_ . _ __ _ 
1.0 
Good_ 
Good_ 
Good_ 
Good. 
Do_I__ 
.1 
None__ 
None_ 
None_ 
None. 
Linseed-oil soap__ ... _ __ __ 
. 1 
Medium. _ 
Poor.. 
Medium __ 
Poor. 
Casein (in Ca(OH )2 sol.)„ . . 
.01 
Good_. 
Good__ 
Good_ 
Good. 
Casein (in NaHCOs)__ _ _ _ _ . _ 
.01 
__do— __ 
___do_ 
...do_ 
Do. 
Milk, skim (fresh) —_ 
1.0 
___do- 
—do_ 
—do__. 
Do. 
Milk, skim (24 hours old) „ _ . 
1.0 
None_ 
None.. 
None_ 
None. 
Milk, skim, plus Ca(OH) 2 __ . 
1.0 
Good. 
Good... __ 
Good_ 
Good. 
Gelatin___ ___ 
. 1 
___do_ 
___do_ _ 
___do_ 
Do. 
Do_ _ 
.01 
Medium. _ 
None_ 
None_ 
None. 
Glue_ _ _ __ 
.1 
Good_ 
Good_ 
Good_ 
Good. 
Saponin bark.. _ ___ 
1.0 
_do... __ 
__do_ 
__do_ 
Do. 
* Do . „ 
/ .1 
Medium. _ 
None_ 
Poor 
Poor. 
Tannin__ _ _ _ 
x .1 
___do_ 
Poor_ 
Medium.. 
Do. 
Gum arabic _ _____ __ 
1.0 
None_ 
None_ 
None_ 
None. 
Pepsin.. . _ _ . 
.1 
Good__ 
Medium __ 
Medium __ 
Medium 
Flour, hard wheat_ __ 
.1 
—do _ 
Good_ 
Good_ 
Good. 
Do_ 
.01 
Medium __ 
Poor_ 
Medium.. 
Poor. 
Agar agar__ _ _ ______ 
. 1 
_do_ 
___do__ _ 
Poor_ 
Medium. 
Dol_ 
.01 
___do _ 
___do 
...do_ 
Poor. 
Blood (water extract) 
1.0 
Good.. . 
Good_ 
Good_ 
Good. 
Do_ 
.1 
Medium. _ 
Poor.. 
Poor_ 
Medium 
Albumin_ _ 
.1 
Good.— __ 
Good__ 
Good_ 
Good. 
Do_ 
.01 
___do_ 
___do_ 
___do_ 
Do. 
Red clover hay (extract) ______ 
2.0 
___do_ 
___do_ 
_ .do_ 
Good. 
Do_ _ _ 
.2 
Medium __ 
Poor. 
Poor__ 
None. 
Vetch hay (extract)_____ 
2.0 
Good_ 
Good_ 
Good_ 
Good. 
Alfalfa hay (extract). _ _ 
2.0 
_-_do_-_ __ 
...do_ 
...do_ 
Do. 
Creosote oil __ ___I 
1.0 
None_ 
None__ 
None_ 
None. 
Creosote, beechwood__ ___ _ 
1.0 
_do_ 
...do_ 
___do_ 
Do. 
Cresol__ ___ _ __ _ _ _ 
.1 
Medium __ 
_ do. 
...do_ 
Poor. 
Evgenol___ _ _ __ 
.5 
_do__ 
...do _ 
Poor__ 
None. 
Phloroglucine___ 
. 1 
Poor_ 
__ do _ 
None... 
Do. 
Guaiacol_ ___ _ 
.1 
___do__ ___ 
_„do. 
...do_ 
Do. 
Resorcin _____^__ 
.1 
-do- .__ 
___do_ 
...do__ 
Do. 
Oil of cottonseed___ 
. 1 
Medium __ 
...do_ 
Poor.. 
Do. 
Oil of cedar _ 
.1 
do ___ 
_ do_ 
do_ 
Do. 
Oil of pears 
. 1 
None_ 
___do_ 
None_ 
Do. 
gravity of 0.869 at 20° C. was selected and observations made on the 
interfacial tension of many substances to the oil. The surface ten¬ 
sion of the oil was 30.4 dynes per centimeter at 25°. 
The apparatus devised by Fahrenwald (2) and used for these sur¬ 
face-tension determinations was used also for interfacial determina¬ 
tions. It is claimed that this is the only instrument made that will 
give fairly true static interfacial tension values. This is important 
in that when a spray issues from the nozzle of the spray gun in drops 
of various sizes it establishes, at least partially, static equilibrium 
by the time it comes into contact with and settles upon the plant 
surface. After contact, static equilibrium is established at the inter¬ 
face of spray solution to* plant surface, quickly or slowly, depending 
upon the spreader solution used. Measurements were recorded 
about 3 minutes after the oil was introduced upon the surface of the 
spreader solution. Table III gives the results of the observations 
made at 25° C. 
