166 EDWIN GILPIN ON LIMESTONES 
(9.) ROBERTSON LIMESTONE.—Dark, earthy blue, compact, argillaceous limestone, with 
numerous fossils and a few small crystals of silica and iron pyrites. 

Moisture 7252 ne nn mien sisi’ niecelaie) nas ee de AE TO OU DO 1:156 
Timo carDOnAte Rene mener le enese actes see semer ere 5900 78-344 
Magnesia carbonate... ..4.,., ...,,,...,...2 races cavece soon sesecn nee trace. 
Iron CMO oos 000 aaodoo adonomodoD Odo00N DOGO Gdo0G deacon aondDs Eee 2:224 
ManvaneseNCarbonato eee eee e--c re -LC eee 4245 
Jon Eritimblocoudecoseondeosdondonoobnoncondeo0 dote nova onda6oco boceon ‘482 
Phosphoric acid......... Dubé Too 850000 danoodIodo0 ngUOoN 5000 done vovt ba doc 0bo “064 
Imsolubleresidue ere nee teisielsiclsteveors eisleleucreeivetsWolereletelelisteisicle Meleter ete teleneiete sets 11:600 
HoNrpoond cooosnoocooobuoncoondoc 96-115 
(10.) Forks LIMESTONE.—Compact, bluish-black limestone, with crystals of calcspar 
and spots of arenaceous matter. 

Moisture ses svst waive eis sata mn nee, alererereiecciavere ae ee tale ee ele daccod. CE) 
Hmercarbonale=erccrcCereree-cPrecccrcte-ecrerectc-ctece-cceececcreeree 791130 | 
NI aAEEY CEN SWANK Goo coad dan Cobos DAAbOG Hoands OBY0O.LdOgdN SéouODdKdOO0EC 2185 | 
IbROyNY (CNA SLE 6000000000 000000 iooorn dite doboon ana one 20000 dec 00000 5619 . 
Manganese oxide................... odd 0000 ANA T00.0A0 000 100000 DOUDOO PIVOT trace. 
Jr poo ASH ands bn Soo ao. cHod0b HONDOD NOUN 100000 2000000009 000000 DDR 495 
on [Spa svK)500 avons ovonnso CoG000 590000. 450NEG 00008 2000181000 000000 adb00e ‘754 
Phosphoric acides eee Ce Ce don PO mation dos Done Jo û 00 couv ‘403 
NAN METEL cocceo odoodo poosvoo deco ob oouaudoonopo gogo 00006 onraac 11-392 
Ron Non decagbonsos c00padoaduddoo 100-308 
(11) SHezr LIMESTONE.—The following are analyses of the “shell” limestone from 
Brookfield and Windsor, referred to in these notes :— 






ComrosiTION. BROOKFIELD. WINDSsOR. 
16 Il. 
TEI MOEUCAT DONA LE slelelstiereretelelelcicletsuelaielslsie tele relelateratsUrialfelele 97°39 98-844 97°64 
Magnesia carbonate...... s.+ere ceenes socers cavers “94 396 1:10 
> (Oratl)o minis one oniononnne 0010 50000 2:70* 2-000 * 07 
Phosphoriciacideeeeesrce-c----ec-r-rcP-eerceere trace. 
Imsoluble residence esse cereecrerreerpl trace. trace. 68 
MOTAL esse csistarsteiatrefsisfeleratteleretstels ei 101-083 101-240 99.49 




* Containing alumina. i 
These limestones, which can be compared most aptly to a heap of recently opened 
and cleaned shells thrown together, are notable for their freedom from phosphorus, 
sulphur, etc., and are apparently little beyond pure carbonate of lime, the iron oxide and 
alumina being carried in mechanically by water from the overlying clays. 
