214 A - S - PACKARD, Jr., ON THE GLACIAL PHENOMENA 



Geological Survey. In coasting within a mile or two of this interesting region we see the 



tianTckfT r ning R ° U * aS a *° W P"»* 0f land «"ti°8 on the lofty, precipitous Lauren- 

 tian rocks Between Bradore Bay and Anse an Loup these sandstones and grits rise up 

 to a height of 500 to 600 feet, forming the coast line; and looking up through th bays 

 and harbors we can see the low conical hills of Laurentian gneiss in the interior At the 

 eastern termination of this formation, the Laurentian rocks rise into high, rugged and 

 broken syemt.c hummocks, in marked contrast with the regular terraces and smoot slopes 

 o the fossmferous sandstones and limestones. Approaching Henley Harbor, there is a visi- 

 ble change in the scenic features of the coast; the hills grow more regular in outline and 

 slope gradually to the water, giving us the peculiar physiognomy of the Laurentian gne" 



Upon entering Henley Harbor the dark gneiss is seen resting upon syenite and at Te 

 point of contact interpenetrated by irregular intrusive masses of the latter rock' On Hen 

 ley Island, where these rocks crop out under the trap capping this island, there appears 



syenite ° ^^ *"* ' ^^ ^^ and ° f the USual fles » color of le 



At this point I broke off some pieces of nearly unratified syenite which showed verv 

 distinctly the sedimentary origin of the rock, for the crystals were often partly rounded 

 and contained rolled quartz pebbles, one being ovate and nearly two inches long TKs 

 syemtic gneiss was evidently an altered conglomerate 



The syenite is the same as occurs on the coast of the St. Lawrence River, and while of 

 the same color as that of the Maine and Nahant syenite, differs in its greater hardne. nd 

 in the absence of black hornblende. It is composed of a flesh-red labradorite or soda feld 

 spar and a smoky and glassy quartz with minute particles of hypersthene disseminated 

 sparsely lirough the mass It is exceedingly tough and durable, as evidenced by the lofty 

 overflow" ° ^ ^ ^ ^ "^ ^^ — d the base of the 



At the northern end of the island the syenitic gneiss dips under the trap in a southeast- 

 erly direction at an angle of 50 On an island a few rods farther to the north! ^ 



"Vn 1 d Tf r ' b ; ing 3 banded -* Kg* and dark strata, and has the^gen 

 eral N. N. E. strike and dip indicated above g 



At Square Island, which lies at the mouth of a deep bay just north of Cape St Michael's 

 occurs m large, conical hills the great ano M e formation of Logan and Hunt, compo ed of 

 large, crystalline masses of labradorite, with a little vitreous quartz, and coarse, ciystaliine 

 masses of hypersthene. The labradorite is of a smoky color, very lustrous, tran Z t and 

 opalescent, with cleavage surfaces often two inches in diameterfand on some of the faces 



^MsssKa ^r o^XTait r e rich bi ue t " 

 asrr- b ^ the E — --- ^^^== 



in dfamete r r k T W b eathe ? ^ ^f *** ^^ ^ CGt " masses so ™etimes two inches 

 in diameter. This rock easily weathers, and large masses are detached bv frosts ° Z I 



ily crumble to pieces. The gneiss rests on the south side of the l^^^Z^t 

 hdls here can be seen huge gneiss mountains at least 2000 feet high rish o- in v3/ n 



i^^if^zr ty ^ s in the — **• - ^tr 



At Cape Webuc or Harrison, the gneiss again appears upon the coast as a lofty headland 



