36 ROYAL SOCIETY OF CANADA 
and contractions of the different grains had served to rend them apart. 
This has an important bearing upon the fact that the co-efficient of 
expansion of the column as a whole changed in the later heatings as 
compared with the first heating.” 
The third and last rock to be examined was a specimen of white 
marble from Carrara, Italy. <A description of this rock is also to be 
found in the article by Dr. Adams and Dr. Coker already referred to, 
pp. 26-27. Itis a “white very fine grained saccharoidal marble. Under 
the microscope it is seen to consist of a mosaic of calcite grains. In this 
mosaic, some grains are larger than others, but there is no great differ- 
ence in their relative sizes and the average grain of the rock is uniform 
throughout. The average diameter of calcite crystals closely approxi- 
mates 0.2mm. The grains come against one another along sharp and 
usually straight lines. There is no trace of foliation in the rock, nor is 
there any trace of flattening or elongation of the grains in any one 
direction. The rock is perfectly massive.” 
The method employed was identical with that in the case of the 
diabase and granite, except that in the present case the heating was not 
carried above about 500° C., as the marble would bé decomposed at the 
higher temperatures. The specimen was roughly cylindrical and its 
length, as measured with the vernier calipers before heating, was found 
to be 19.925 ems. at room temperature. 
The results obtained during the six heatings are given in the follow- 
ing tables (See also Figure VI.) 




Results of First Results of Second Results of Third 
Heating. Heating. Heating. 
Tempera- | Total Ex- Tempera- Total Ex- | Tempera-| Total Ex- 
ture. pansion. ture. pansion. ture. pansion. 
22°C. QO mm. 18°C. .732 mm. 16°C. .897 mm... 
162 .221 128 .788 146 .959 
273 .667 199.5 .861 358 1.499 
338 .976 340 1.309 430 1.716 
387 1.234 414.5 | 1.530 463 1.852 
448 1.011 455.5 | 1.711 19 .952 
19.5 .732 464 OO Se 
ns ag din NL are ate Pala Reale 16 .897 MS Sisters À 


