. Economic Papers. he end, as shown in figure 16, A. Irregularities inthe formation were encountered at several places. At 1, figure 16, A, asmall lens or streak of pegmatite cuts across the hornblende gneiss walls ofthe tunnel. At 2 there is a vertical contact of hornblende gneiss on the leftand pegmatite on the right. For a number of yards at 3 there is hornblendegneiss in the bottom of the tunnel and pegmatite in the upper part. At 4the pegmatite gives out and hornblende gneiss is encountered. The irregu-lar nature of this contact is shown in figure 16, B, which represents the sec-tion (a)
. Economic Papers. he end, as shown in figure 16, A. Irregularities inthe formation were encountered at several places. At 1, figure 16, A, asmall lens or streak of pegmatite cuts across the hornblende gneiss walls ofthe tunnel. At 2 there is a vertical contact of hornblende gneiss on the leftand pegmatite on the right. For a number of yards at 3 there is hornblendegneiss in the bottom of the tunnel and pegmatite in the upper part. At 4the pegmatite gives out and hornblende gneiss is encountered. The irregu-lar nature of this contact is shown in figure 16, B, which represents the sec-tion (a) exposed on the south wall. The feldspathic part of the pegmatiteforks into mica gneiss. At 5 and 8 there are irregular streaks of massivequartz. Between 6 and 7 there is a vertical contact between pegmatite andhornblende gneiss. At (&) there is another large irregular mass of quartzincluded in or a part of the pegmatite. It is shown in cross section in figure16, C, as it appears in the north wall of the JDiifrip 50
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Keywords: ., bookcentury1900, bookdecade1910, bookideconomicpape, bookyear1912
