rtll.LKC I'lONS 1\ KCnNoMlc (ilidl.fXlV A M > N! KTA l>M K'fi Y. 2.T5 



iKMHiriillv foiit.iiiis \A\'^r Miiiniiiils ol iiiiin-i'.il iiiattiT, iiiaiiily sainl llial 

 was ItUtwii onto tlu' ;^r(t\\ iii;^ moss. Ijar;;i' deposits arc loiiiid in Ireland. 

 It is used as a fuel and also as a fertilizer. Altlioiij^h its fuel value 

 is low, when it occurs in regions destitute of other fuels it hecoiucs 

 very useful. This is the case in sevi'ral northern countries. 



Peat is illustrated by a siuirh' speciruiMi from a northern island where 

 there is no coal or wood, driftwood l)ein;; the onl> fuel lor the natives. 



{I) CoiiiiiuukIi T Island, IJchiin;^ Sou, cast of Kaiiiciiiitkii. ( .V.HWi i. ) 

 • Tbe tlioroii^Iily air iliii'il inatt'iial slio-M'd on analysis: 



I'rr <:«'nt. 



Wator 7. ()0 



Volatilo matter r>l.l>7 



Fi \vd cai bou 2*2. CM i 



Ash , 18.37 



100.00 

 Analyst. Dewey. 



Bitumen Series. 



Umler this head is <;rou|»ed the series of iiydrocarlxuis l>e<;inning 

 with tbe solitl asphaltum and foUowiug through semi-solids to liquid 

 petroleum aiul ending with natural gas. The niemhers of this series 

 consist of mixtures of various hydro-carbons, many of which contain 

 much oxygen. The solids naturally graduate into the liquids and the 

 li(|uids fre(iuently change into the solids through the loss of volatile coit- 

 stituents, and sometimes by the absorption of oxygen. 



The physical condition is often atfetjted by temperature, and a speci- 

 men that is solid in winter may be semisolid or even liquid in summer. 

 Most of the specimens, particularly of the solids, are black or dark 

 colored: but many of the petroleums are light colored, while natural 

 gas is gciierally colorless. 



St (LID IJITIMENS. 



ASCUAI.TfM. 



(Jom])osition : A mixture of various hydro<rarl)ons. 



It is amorphous, and the specitic gravity varies from 1 to 1.^ or more, 

 depending upon impurities. It has a characteristh* luster and o hu'. It 

 is black in «-olor and melts at ♦JO-' to 1(K>J ( '. 



It is found in rocks of all ages, but there are only a lew dejiosits of 

 large ext«'nt. The most noted locality is on the island of Trinidatl, 

 where there is a lake of it l.\ miles in circumterence, which is hot and 

 litpiid in the (renter, but grows cold ami hard toward the edge. Large 

 (piantities are taken from this lake. 



The jdiiicipal use ol' asphalt is in making pavements lor roa<ls and 

 walks. It is illustrated l>y t wo specimens . 



(1) In trap rock. Ilai ilord. Connicticnt. (.'•'.•'.KM.) 



(2) Ma»sive. Island <>f Trini<la<I. (10tJ78.) 



