Feb., 1917
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY
made without. I n fact, all breads, whether made with a m m o n i u m salts or n o t , give a slight; coloration if Nessler solution is applied t o t h e crumb. It was found, however, t h a t cheese, eggs, cakes, salt-rising bread, meat and meat extracts, a n d particularly saliva, gave very positive tests for ammonia with Nessler's reagent. E v e n compressed yeast gives a n u n mistakable test for ammonia. Tests for ammonia in a commercial bread made with t h e yeast food containing ammonium chloride a n d other breads bought in t h e market were made according t o t h e directions given b y Prof. J. C. Summers' i n a paper before t h e members of t h e National Association of Master Bakers at Salt Lake City a n d b y distilling a water extract from these breads with MgO. T h e results are given in Table 11. TABLE 11-TEST
AMMONIA O X V A R I O y S BREADS Per cent Ammonia Per cent Ammonia NO. (Nessler Solution) (Distilled with MgO) 0.0040 0.0045 3 (made with yeast food).. . . . 0.00008 0.0045 0,00016 0,0040 0.00012 0.0040 0.0051 7 Salt-rising.. . . . . . . . . . . . . . . 0.00024 0.0153 8 Yeast.. . . . . . . . . . . . . . . . . . . 0.00024 0.0085 FOR
Bread
.. .. .. ..
Although t h e method given b y Prof. Summers is not t o be recommended for determining t h e absolute q u a n t i t y of ammonia i n foods, i t nevertheless gives valuable comparative results. T h e results from this laboratory show t h a t t h e bread made with a yeast food containing ammonium chloride gave t h e lowest value for ammonia when comparing t h e color produced with Nessler solution against t h e color produced i n a s t a n d a r d ammonium chloride solution. 0 . n t h e other hand, i t will be seen t h a t salt-rising bread a n d compressed yeast give high results for ammonia by both tests. E v e n when a short process of fermentation is used t h e quantity.of ammonium chloride left in t h e bread is insignificant. Experiments were made using increasing quantities of yeast a n d decreasing periods of fermentation. I n only t h e most extreme case, where t h e dough was fermented only I hour, could traces of t h e ammonium chloride be foKnd. Table I11 shows t h e q u a n t i t y of yeast used, with t h e time of fermentation given t h e dough a n d t h e ammonia recovered from t h e baked bread. I n each case j 6 0 grams of flour were used a n d 4 grams of yeast food containing 0 . 3 2 1 gram NHdC1. T h e ammonia added i n t h e form of ammonium chloride a n d figured on t h e dry materials of t h e bread was 0 . 0 1 9 1 per cent.
ing 5 0 grams of d r y material was broken u p under water immediately when mixed, a n d another after standing 5 hours, t h e a m o u n t of ammonia as ammonium chloride recovered i n each case being 0.723 gram. Deducting from this 0.135 gram, t h e equivalent of ammonium chloride obtained from a dough containing no added ammonium salt, we have 0 . 5 8 8 gram, or almost t h e complete quantity, 0 . 5 9 2 gram added. T h e following experiment shows t h a t ammonium chloride does not stimulate t h e gas production of yeast in a cane sugar solution, using distilled water. If t h e ammonium chloride merely accelerated t h e gas production this experiment would demonstrate t h a t fact. We were unable, however, t o obtain a n y increase i n total gas production repeating this experiment a number of times. This would indicate t h e n t h a t t h e ammonium chloride is utilized only a n d exercises a favorable increase in gas production only when there is a reproduction of new yeast cells. Under t h e conditions of this experiment there can be only a very limited reproduction since t h e necessary elements-phosphorus, potassium, calcium a n d magnesium-are lacking. However, in t h e dough we have these elements present a n d therefore get a tremendous increase in t h e q u a n t i t y of gas produced as t h e experiment below indicates. EXPERIUEKT
16
32 40
Fermentation of Dough 5 hrs. 3 18/4
1
Min. in Proof Box 51 41 33 33
Weekly, 18, 37.
THE
EFFECT
OF
A31XOKIUM
SGGAR SOLCTIOK
For t h e t e s t , zoo cc. distilled water, 4 grams yeast a n d 2 0 grams of sugar were 'used. Temperature, 28'
c.
......
Grams Ammonium Chloride.. 0 Cc. Gas Produced (61/2 hre.). . . . . . . . 830
0.16 815
0.32 800
0.64 800
E X P E R I M f i N T S H O W I N G T H E I N C R E A S E I N GAS P R O D U C -
TION IN D O U G H , USING Fermentation Hrs.
NH4Cl
Control Dough Cc.
Dough containing 0.2 g. DIFFERENCE N H L l per 100 Flour DIFFERENCE 0 110 cc. 0 80 180 80 280 105 100 390 105 110 80 500 110 100 640 140 95 785 145 125 170 955 90 1105 150 100 1260 155 100 1400 140 80 1520 120 70 105 1625 1120 cc. 1 5 1 5 cc. ammonium chloride.. . . . . . . . . . . . . . 35 3 CHEMICAL LABORATORY WARDBAKINGCOMPANY NEW YORK CITY
.......
SYRUPS FOR CANNING AND PRESERVING Per cent Ammonia D r y Bread 0.0045 0.0051 0.0051 0.0062
To show t h a t t h e ammonium chloride is not consumed b y t h e enzymes of t h e flour or bacterial action, t h e following experiment was carried o u t : A dough was made of t h e same formula as previously used except no yeast was added. This dough contained 0 . j g 2 g r a m ammonium chloride. A piece of dough contain-
' Bakers'
SHOWIXG
C H L O R I D E O N T H E GAS P R O D U C T I O S IS A CANE
TABLE I11 Yeast Grams 8
151
By JAMES
B. M C N A I R
Received October 30, 1916
I n t h e canning of most fruits, syrups are used of 20, 30, 40, 5 0 or 60' Balling or Brix. Some packers, however, use about 2' less for each grade, while others use s y r u p of 15, 2 j a n d 5 5 ' . T h e degree of syrup is arbitrary with t h e packer a n d is not indicated on t h e can label. T h e strength of syrup used is governed b y four main factors, viz., t h e acidity of t h e fruit, t h e q u a n t i t y of t h e fruit, fruit shrinkage or shriveling, and t h e flavor IO,
T H E J O C R Y A L O F I , V D L T S T R I d L A N D E L V G I N E E R I ~ V GC H E M I S T R Y
I52
desired. Fruit of high acidity requires a high percentage of sugar, a n d vice versa. Fruit of delicate flavor requires less sugar t h a n strongly flavored fruit. T h e importance of having syrup of uniform strengths is not fully appreciated b y f r u i t canners. Samples of syrup t a k e n f r o m a number of factories, without t h e TABLE I-EXAMINATIONOF SYRUPSI N USE Standard (Balling).. , 60 Highest Found . . . . . . . 6 0 . 9 Lowest F o u n d . . . . . . . 60.1 AVERAGE.. . . . . . . . . 60.6 Number of Samples: Total . . . . . . . . . . . . . . . 4 Abovestandard.. . . . . 4 Below Standard . . . . . . 0
55 50 57 52 37 49.6 49.5 5 0 . 2 9 3
5
3 I 2
AT
CANNERIES TOTAL 15 10 ,, ,
40 43.9 25.7 37
30 34.2 18.4 28.8
20 21.5 21 21.5 12.6 10.3 6.1 2 1 . 6 14.8 10.3
... ...
37 11 24
51 14 31
4i 15 28
2!6
22 8 12
43 21 10
...
122
1-01. 9 , No.
2
pler methods must be used t o obtain t h e correct results. I n m a n y factories a concentrated syrup is first made which is diluted t o t h e various strengths t h a t t h e specific f r u i t m a y require. T h a t t h e methods used i n this dilution are insufficient or poorly applied has been shown above. K i t h these facts i n mind experiments were conducted on a small scale with a view of removing Or lessening these inaccuracies' Tables 11 t o v are t h e result. I t is hoped t h a t these tables, which have proved reliable on a small laboratory scale, will be found useful for large scale aDDlication. T h e accompanying curves a n d Table V I point out t h e error of t h e formula s = ( 6 j - a)v/g j , which was inserted in a previous publication.' Y
knowledge of t h e syrup maker, show t h a t there is a marked lack of uniformity i n syrup strength. Table I summarizes t h e results of a n invesTABLE 11-SHOWING GALLONS O F WATER Desired Brix Degree:
0
0 5 10. . . . . . . . . . . . . . . . . . . 15 ......... 20 ......... 25 ......... 30.. . . . . . . . . . . . . . . . . . 35.. . . . . . . . . . . . . . . . . . 40 ......... 45 50 55................... 60, . . . . . . . . . . . . . . . . . . 65. . . . . . . . . . . . . . . . . . .
5 7.1
__ 0.98 2.00 3.08 4.25 5.47 6.81 8.18 9.58 11.1 12.5 13.9 15.7
O R OUXCES O F S U G A R PER GALLON O F SYRUP REQUIRED TO CHANGE A SI'RUP FROM ANOTHERGIVENDEGREEBRIX AT 17O C. (SEE EXAMPLES BELOW) 4bove dashes read: "Ounces of..Sua* I Added ber Gallon of Svrub" 10 I5 20 25 30 50
14.5 7.2
o.si.1 ..... 1.062 1.650 2.27 2.94 3.63 4.35 5.10 5.80 6.53 7.44
22.7 15.1 7.7
-
32.1 24.2 16.5 8.5
43.0 34.: 26.i 18.4
134.9 123.8 113.0 101.8 89.8 76.9 63.0 48.2 32.7 16.7
55.8
47.z 38., 30.0 20.7 10.7
A
GIVENDEGREEBRIXTO
55 172.2 150.3 138.6 126.5 113.7 99.8 84.8 68.8 52.0 34.7 16.7
0.364 ___ 9.5 0.752 0.284 __ 1.164 0.587 0.235 __ 1.608 0.912 0.488 0.206 2.06 0.748 0,419 1.246 2.54 1.597 1.023 ' 0 , 6 3 9 3.03 1.960 1.307 0.870 3.50 0.115 2.30 1.570 1.086 3.98 0.232 0.104 2.66 1.850 1.305 4.58 1.562 0.355 0.211 ?'.OS 2.17 Below dashes re6rd: Gallons of Waier Added EXAMPLE 1: To change a syrup of 5' Brix at 1 7 ' C. to a syrup of 10' Brix at 1 7 O C . , add 7.2 02. of sugar per gal. of syrup. EXAMPLE 2: T o change a syrup of 10' Brix at 17' C. to a syrup of 5' Brix at 17' C . . add 0.98 gal. of water for every gal. of syrup. O F WATEX O R OUBCES O F SUGAR PER OUNCES O F S U G A R O R GALLONS O F WATER I N SYRUP RE:QUIRED TABLE111-SHOWING! GALLOXS FR:OM A GIVEN DEGREEBRIX TO -4NOTHER GIVEN DEGREEBRIX AT 17' c. Above dashes read: "Ounces of Sugar Added peu Gallon of Water in Syrup" 10 15 20 25 3n 35 40 4.5 so 5 55 Desired Brix Degree: 0 - 7.1 1475 22:7 32:l 43:O 5i:8 109;7 134:9 ii:O 88:: 162.2 0.
........ . .
__
7.4
.. .. ....... . ..
~
TABLEIV-CHANGE I N VOLUME(IN PARTSPER l0.000) OF SYRUPSAT DIFFERENTTEMPERATURRS Temp. loo 20° 30° 40° 50OBrix c. 16 I 9 12 5 4.5 15 20 25 30 35 40 45 50 55 60 65
-i o_ i:,
80
85
90 95 100
16 28 41 57 74 92 112 134 156 183 209 236 265 295 325 355 387 418 450
65 231.6 224.5 217.1 208.9 199.5 188.6
175.8
~
........ ..
12 21 33 48 64 82 101 122 145 170 197 225 255 284 316 347 379 41 1 442
CHAXGB A SYRUP
~
....... ........ ..
10
-
0.094
15.6 8.2
.......
EXAMPLE 2:
65 231.6 218.5 203.6 189.5 174.4 157.8 140.0 121.3 101.1 80.6 59.3 39.5 19.4
60 194.6 25.0 127.8 155.1 35.9 48.7 Bl., 102.6 187.5 63.9 .. 0.072 -17.6 28.5 56.5 74.3 95.2 120.4 180.1 147.7 41.3 139.5 0.097 0.0249 - 9 . 4 20.3 33.1 48.3 66.1 87.0 112.2 171.9 130.1 0.0379 0.0130 -10.9 77.6 102.8 . . 0.110 23.7 38.9 56.7 162.5 91 . Y 119.2 0.0458 0.0209 0.0079 45.8 66.7 151.6 0.118 12.8 28.0 79.1 106.4 0.0511 0.0262 0.0132 0.0053 ___ 15.2 33.0 53.9 138.8 . 0.123 0.0549 0.0300 0.0170 0.0091 0.00384 17.8 38.7 63.9 91.2 123.6 0.127 . , 0 , 1 3 0 0.0577 0.0328 0.0198 0.0119 0.00666 0.00282 - 2 0 . 9 46.1 73.4 105.8 52.5 84.9 . , 0.132 0.0599 0.0350 0.0220 0.0141 0.00880 0.00496 0.00214 ___ 25.2 0.0616 0.0367 0.0237 0.0158 o.01051 0,00667 0.0038s 0.00171 59.7 27.3 0.134 ,, 0,135 0.0628 0.0379 0.0249 0.0170 0,01176 0.00792 0.00510 0.00296 0.00125 32.4 0.00227 0.00102 0.00398 0.136 0.0639 0.0390 0.0260 0.0191 0.01278 0,00894 0.00612 0.00309 0.00184 0.00082 0,00480 .. 0.137 0.0647 0.0398 0.0267, 0.0189 0.01360 0.00976 0.00694 Below dashes read: Gallons of W a f e r Added fier Ounces of Sugar an Syrup" To change a syrup of 5' Brix at 17' C. to a syrup of l o o Brix a t 17O C., add 7.4 02. of sugar per gal. of water in syrup. To change a syrup of 10' Brix at 17' C. to a syrup of 5' Brix at l i 0 C., add 0.072 gal. of water per 02. of sugar in syrup.
........
5. 10.. . . . . . . . 1 5 . . ....... 20.. . . . . . . . 25 . . . . . . . . . 30.. 35.. 40..... .... 45. . . . . . . . 50. 55.. 60. 65 .........
EXAMPLE1 :
TO
60 194.6 181.6 169.0 155.9 142.0 126.9 110.6 93.3 74.9 56.2 36.6 18.4
21 34 49 66 84 103 124 146 170 196 222 249 277 306 335 365 395 425 456
26 42
58 75
94 114 136 160 184 210 235 26 1 287 316 345 375 405 435 465
32 50 69 88 110 132 156 180 204 229 253 278 306 332 360 388 417 445 473
TABLEV-CORRECTION Temp, O C.
-
THE READINGSO F BALLING'SSACCHARIMIBTER, ACCOUNT O F TEMPERATURE PER CENT OB SUGAR IN SOLUTION-15 20 25 30 35 40 50 60 70 75 0.21 0.22 0.24 0.26 0.27 0.28 0.29 0.33 0 . 3 5 0.39 To be 0.17 0.18 0.19 0.21 0.22 0.22 0.23 0.26 0.28 0.32 Subtracted 0.14 0.14 0.15 0.16 0.17 0.16 0.17 0.19 0.21 0.25 from 0.09 0.10 0.10 0.11 0.12 0.12 0.12 0.14 0.16 0.18 the Degree Read 0.03 0.03 0.04 0.04 0.04 0 04 0.04 0.05 0.05 0.06 FOR
13 14 15 16 17
0.06 0.07 0.08 0.02 0.02 0.03
18 19 20
0.02 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.06 0.08 0.08 0.09 0.09 0.10 0.10 0.10 0.10 0.10 0.11 0.14 0.15 0.17 0.17 0.18 0.18 0.18 0.19 0.19 0.16 0.20 0.22 0.24 0.24 0.25 0.25 0.25 0.26 0.26 0.21 0.26 0.29 0.31 0.31 0.32 0.32 0.32 0.33 0.34 0.27 0.32 0.35 0.37 0.38 0.39 0.39 0.39 0.40 0.42 0.32 0.38 0.41 0.43 0.44 0.46 0.4G 0.47 0.47 0.50 0.37 0.44 0.47 0.49 0.51 0.53 0.54 0.55 0.55 0.58 0.43 0.50 0.54 0.56 0.58 0.60 0.61 0.62 0.62 0.66 0.49 0.57 0.61 0.63 0.65 0.68 0.68 0.69 0.70 0.74 0.56 0.64 0.68 0.70 0.72 0.76 0.76 0.78 0.78 0.82 0.63 0.71 0.75 0.78 0.79 0.84 0.84 0.86 0.86 0.90 0.70 0.78 0.82 0.87 0.87 0.92 0.92 0.94 0.94 0.98
26 27 28 29 30
tigation b y Dr. A. W. Bitting, entitled "Methods Followed i n t h e Commercial Canning of Foods," a n d printed as U.S. Dept. of Agriculture, Bureau of Chem-, istry, B d . 19% M a y 2 9 , 1915. This table Plainly evidences the fact that syrup as used in many tories is either not made with sufficient care or t h a t sim-
-
ON
0 5 10 0.14 0.18 0.19 0.12 0.15 0.16 0.09 0.11 0.12
21 22 23 24 25
-_
160.6 142.8 121.9 96.7 69.4 37.0
0.03 0.03 0.02 0.10 0.08 0.06 0.18 0.15 0.11 0.25 0.22 0.18 0.32 0.29 0.25 0.39 0.36 0.33 0.46 0.43 0.40 0.54 0.51 0.48 0.62 0.58 0.55 0.70 0.65 0.62 0.78 0.72 0.70 0.86 0.80 0.78 0.94 0.88 0.86
To be Added to the Degree Read
s = grams sugar necessary t o bring t o 6 j " Brix. a = degree Brix of syrup.
v = volume of syrup in cubic centimeters. Dilution Tables I1 a n d I11 mere made b y t h e use 1 W. V. Cruess and J. B. McNair. "Jelly Investigations," THIS JOURNAL, 8 (1916). 417.
F e b . . 191j
T H E .TOrRSilL OF INDrSTRIAL A N D EN GISE E RI Y G C H E M I S TR Y
+
of the formula in Table l r I ; namely, y = 1 . 4 . ~ o.oozj12s~. where n: = degrees Brix of syrup a n d y = t h e ounces of sugar added per gallon of water a t 1 7 ' C. This last formula mas obtained b y interpolation of experimental results. One of t h e practical applications of these experimental results is shown in connection with fruit jellymaking. I n determining t h e amount of sugar necessary t o add t o a fruit juice or extract for 3elly making no compensation need be calculated for extracts of less t h a n I j o Brix. 'The right amount of sugar in ounces (more t h a n 60' and less t h a n j z o Brix) may be obtained by adding I . 8 times t h e number of ounces of fruit extract.' TABLEVI OVSCES S C G A R PER GAILOS O F WATER A T l i 0 c. Calculated by McNair y = 1.41P e r cent Observed 0.0025 121-3 Calculated by ' Cruess and hlcNair by (where x = Sugar 1 7 0 c. Bitting degree Brix) s = (65 - a)8!35 0 0. . . . . . . . . . . . . 0 0 .......... i i.064 19.0 10 . . . . . . . . . . . . . 14.8 14.512 38.1 15.. . . . . . . . . . . . 23.5 22,728 57.1 20 . . . . . . . . . . . . . 3 0 . 8 32.096 76.2 75............. 43 . 0 44.5 95.2 114.3 30 . . . . . . . . . . . . . 57.12 55.824 i0.952 133.4 35.. . . . . . . . . . . . 7 1 .i5 152.4 88.768 40 . . . . . . . . . . . . . 8 8 . 8 171.5 4 5 . . . . . . . . . . . . . 109.0 109.656 so . . . . . . . . . . . . . 133.3 134.9 190.7 55 . . . . . . . . . . . . . 163.9 162.184 209.8 228.6 6 0 . . . . . . . . . . . . . 200.0 194.592 247.9 6.5, . . . . . . . . . . . . . . 231.608 273.616 7 0 . .. . . . . . . . . . . . .
+
__
The author n-ould like t o express his gratitude t o Professor T. Brailsford Robertson anti Assistant Professor William l-. Cruess for assistance during this i ny e st 1gat i o n . P. 0. B o x I25 BERKELEY CALIFORNIA
BANANA STALKS AS A SOURCE OF POTASH By H. IS. BILLIXGS A N D A. a'. CHRISTIE
possible treatment of such material for the recovery of its potassium suggested t h e following experimental work. SATURE O F VATERIAL-The material used comprised individual banana stalks obtained from fruit markets after removal of t h e fruit. The stalk is of a n endogenous nature, with its vascular bundles SO arranged as to form a collection of tubes through which t h e sap flows. Such a structure permits of very rapid drying. The stalks varied in weight from z t o 4 lbs.. averaging about 3 lbs., and were found t o be \-ery constant in moisture, ranging from 9 1 . z t o 9 2 . 6 per cent water C 0 3 I P O S I T I O S O F D R Y xaTTER-The stalks were chopped into pieces about one in. long and dried in t h e oven. The dried samples were exceedingly friable and easily broken or ground in a mortar. A sample was analyzed for fertilizing constituents with t h e following results : Per cent T o t a l nitrogen ( S ). . . . . . . . . . . . . . . . . . . . . . . . . . . 0.44 Total phosphoric acid (PzOa). . . . . . . . . . . . . . . . . . . 0 . 4 2 Total potash (Kz0). . . . . . . . . . . . . . 10 46 Water-soluble potash (KzO), . . . . . . . . . . . . . . . . . . 7 . 72 Moisture.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.05
T h e d r y matter is as rich in potash as commercial kainit a n d may be considered nearly as valuable, since 74 per cent of t h e potash is soluble in water. Were this material used as a fertilizer, i t is reasonable t o assume t h a t t h e organic matter would in time decompose in t h e soil with t h e formation of humus, resulting in t h e subsequent release of t h e remainder of t h e potash in an available condition. This material also approximates t h e composition and value of dried kelp,' which a t the present time is being used t o a considerable extent as a filler in commercial fertilizers. I n certain respects, t h e material under consideration is probably superior t o kelp for this purpose. Especially t o be noted is t h e fact t h a t banana stalks contain only very slight amounts of sodium and chlorine whereas kelp contains such quantities as t o throw it into t h e class of kainit or other chlorinated salts. E X T R A C T I O X O F SrlLTs-lYeighed amounts O f t h e dry matter were charred sufficiently t o destroy organic matter and t h e resulting char leached with 'successive small portions of distilled water. About 16 per cent of t h e dry matter was recovered in t h e form of watersoluble salts. X maximum yield was obtained with water representing j times the weight of original dry matter. The salts were dried t o constant weight a t 100' C . ! and analyzed with the following results:
Received S o v e m b e r 27. 1916
The great demand for potash salts during t h e past two years has led t o t h e in\-estigation of many materials, occurring either naturally or as waste products. with a x-iew t o t h e possible commercial utilization of their potash content. Ellis.? in a n ash analysis of t h e banana stalk, called attention t o t h e surprisingly high percentage of potash in this material. I n every large American city thousands of these stalks are discarded as garbage weekly. T h e I J. B. MclL,air, "Failures in Jelly Making a n d Their Remedies," The California Culiii'afor. No. 26, 46 (1916). 736. 2 J. Soc. Ciaern. Ind., 35 (1916). 456.
153
Silica (SiOz), . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Iron oxide (Fe90zi.. . . . . . . . . . . . . . . . . . . . . . . . . . . Alumina ( h h O 3 ) .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manganese oxide (MnsOl), . . . . . . . . . . . . . . . Lime (CaO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Magnesia (Rig()). . . . . . . . . . . . . . . . . . . . . . . . . . . . Potash (K 20). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
...........................
...........................
......................... Carbonic acid ('201.). Chlorine (CI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Phosphoric acid ( P d l j ) . . . . . . . . . . . . . . . . . . . . . . . Total per cent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
...
Per cent 2.81 Sone None h'onr 0.12 0 .0 i 64.23 0 46 4.17 26.11 1.57 0.34 99.88
T h e above figures show t h a t the leached salts consist of over 90 per cent potassium carbonate. This salt should command a price equal t o t h a t quoted for any 1
Calif. Agr. Expt. Sta., Bull. 248.
