m 
Seim tific IntcUig ence. 
colouring matter readily. Figures, fruits, &c. cut of this marble, 
and penetrated with colours by means of heat, have a very 
agreeable appearance, and in durability of colour resemble the 
variegated marble paintings found in the Temple of Nemesis at 
Ramno, and in other places. 
27. Chemical Analysis of Tabular Spar by Rose . — He gives 
the following as the constituent parts of the tabular spar of Per- 
heniemi in Finland. 
51.60 Silica, containing - 25.93 Oxygen. 
46,41 Lime, containing - 13.03 Oxygen. 
A trace of Oxide of Iron. 
1.11 Intermixed particles of actynolite. 
99.12 
This tabular spar is therefore a bisilicate of lime, and has the 
same chemical constitution as augite. 
Rose remarks, “ The forms of augite and tabular spar are dif- 
ferent ; the angles of the prism of augite is 92° 18', and 87° 42'. ; 
but on tabular spar, on the contrary, according to the measure- 
ment of his brother, they are 95° 18', and 84° 42'. 1 ’ This fact, he 
further remarks, is striking, although it is not solitary. Calc-spar 
and arragonite have the same composition, but differ in form ; 
also garnet and vesuvian, and iron-pyrites and spar-pyrites. M. 
Mitscherlich has found that an artificial salt, the acid phosphate 
of soda, can crystallise in two different forms. This appearance 
seems to depend on a different arrangement of the individual 
constituent parts, by which not only different forms, but also 
different chemical properties may take place. The augite, for 
instance, is not attacked by acids, while they decompose the ta- 
bular spar with ease. This appears to be connected with the 
different relations to acids, which Berzelius has observed in ma- 
ny bodies which have been exposed to heat, or are in their un- 
altered state ; for example, in the gadolinite, zircon earth, the 
oxide of chrome, and many antimonial salts. 
28. On the Calaite , or Turquois of Persia, and the Lazulite. 
--Berzelius finds that Calaite is a compound of phosphate of 
alumina, phosphate of lime, silica, oxide of iron, and oxide of 
copper. The Lazulite is a compound of phosphate of alumina, 
phosphate of manganese, and of phosphate of iron and oxide of 
iron. 
