346 
greatly, and evidently it varies more in the case of such local 
factors as the decomposition of the rocks, than does the spe- 
cific gravity of rock powder. Even slight decomposition will 
generally lower perceptibly the specific gravity of the powder, 
but by sometimes filling the pores and sometimes enlarging 
them in different cases it affects the porosity very differently. 
The sandstone, the specific gravity of which is entered in 
the last line, has been taken from the great sandstone fragments 
which are inclosed in the augite-syenite at Iviangusat (see p. 51). 
| Specific Weight 
| gravity pr. cm? 
(powdered (whole 
rock) specimens) 
| 
| 
|| 
Stratified part of the batholite : 
Arfvedsonite-granite, Ilimausak (very fresh, greenish) 2272 2°70 
Arfvedsonite-granite, [limausak (fresh, brownish) . . 2°66 2°65 
Pulaskitey N 2S1orarsuit 4% ee eee ne | PUS 2:69 
Koyaite, Naujakasik ran anne ee ee | 2°67 2162 
Sodalite-foyaite, Tupersuatsiak .................. | 2:65 2°59 
Naujaite,#Kangerdluarsuk 2. 2 we 2°53 2:51 
Ægirine-lujavrite, Nunasarnak................... | Ro 2°70 
Arfvedsonite-lujavrite, Nunasarnak ............... | 2:79 2°76 
Kakortokite, white, Kringlerne................... 2216 eagle 
Kakortokite, black, Kringlerner о. | 3°12 3°05 
CREE SES - re |  ——— 
Unstratified complex : 
Nordmarkites Narsakeyee m ve ee 2°74 2°66 
Augite-syenite, Nunasarnausak .................. | 21 2:74 
Essexite SINATSAK Ay are TA N Eh eae a ae | 2:90 2°87 
Sandstone, quartzitic, Iviangusat................ 266 | 2°64 
