EXPERIMENTAL WORK WITH RAW ROCK PHOSPHATE. 7 
obtained by the latter investigator in determining the solubility of 
the calcium phosphate (Ca,(PO,),,H,O) in carbonated waters and 
in water containing both calcium carbonate and carbon dioxide are 
given in Table I. 
ee I.—Solubility of lime phosphate in water containing carbon dioxide and 
calcium carbonate. 
Phosphoric Lime 
Solvent. acid (P20;) | (CaO) per 
per liter. liter. 
Mg. Mg. 
AVA GOT ete ere are SIC Kia ctain b eiwlaldinie ale aie winidielaicie tars o baci a aoe Aoraneabeinwsicceaoos ad ON4olAceeatae ewe 
1,200 cubic centimeters distilled water and 50 cubic centimeters water saturated | 
AVL ©! ©) pe sete ctacia ces eit a(t sien sistas Siege sok lacias hee a hsceee wis ck aoe bes OY eesaceeoadce 
1,000 cubic centimeters distilled water and 250 cubic centimeters water satu- 
mate Guwill Wa © O erase sees oe isteeo enn cite ce qiaanetsicie minnie oe aoe Be ation oasis ASS 5 jane cae cone 
1,250 cubic centimeters water saturated with COo.........-..--...---------2--e-- OUS94T ie ee ee 
Water containing 174 milligrams CaCO; and 82 milligrams COz per !iter........ 88 | 100.0 
Water containing 290 milligrams CaCO; and 171 milligrams CO» per liter_..... ileal 162.3 
Water containing 389 milligrams CaCO; and 270 milligrams COz per liter...... . 80 218.8 
Water containing 488 milligrams CaCO; and 415 milligrams COs, per liter...... 1.77 273.3 
Water containing 558 milligrams CaCO; and 541 milligrams COs per liter...... 1.30 312.7 
It will be seen that the presence of carbon dioxide in water increases 
greatly the solubility of tricalcium phosphate, but that the addition 
of calcium carbonate depresses the solubility of the phosphate. This 
experiment was apparently conducted with samples of relatively 
pure materials, and no doubt the lime phosphate was in a precipi- 
tated form. Under such conditions a greater quantity of phosphoric 
acid (P,O,) would be dissolved than from the same quantity of 
natural rock phosphate. 
An experiment to test the solvent power of carbonated waters on 
various phosphatic materials was conducted by Williams’ many 
years before the one just cited. The results of this experiment are 
given in Table IT. 
TasBLE 11.—Solubility in water of various phosphatic materials used as fer- 
tilizers. 
Water re- 
: quired to 
Source of phosphate. dissolve one 
part of the 
phosphate. 
Parts. 
Apatite from Perth, Canada, containing 89.27 per cent Ca3(PO4)o.......-------------+------ 222, 000 
Seabrrepe eau AOC age en ae ew eee eae se eneine veisinin cemeemnes qo ae-nsinie= se eaiacace 140, 000 
Finely ground bone containing 56.78 per cent Ca3(PO4)o.....---.---------------2-22-2------- 5, 698 
Same, calcined to burn out organic matter, 92.88 per cent Cas(PO4)o---.-..--------------- 8, 029 
Adulterated commercial bone dust containing 24.32 per cent organic and volatile matters 
ein! Ss tap Gomi One? OA PEE Sec cacoos bodgadausc cb eels SeeGa noe sooE Eo ooecsuaedapeceacscanae 4,122 
South Carolina phosphate containing 57.89 per cent Ca3(POx)o.....--.---------------------- 6, 983 
SEG, WTR TOG Ces es eee Be ARR BORE SoC RO SRB DE EE SERCH EORACCOCOCCRECECOE Be pEEDernece Gee 6, 544 
Guano containing 49.67 per cent Caz(PO4)o....-----ccccccccccecn seen eee seen eet e nee e ee eeeee| &, 009 
i1Chem. News, 24, 306 (1871). 
