146 i!i;ii!Lix(; axij salixgku. 



Cliciiiical aualyisis of muiihei- S sampled on the eleventh da}' gave: 

 Ta1!LE \'I1. — Anoli/sis on clevejilli dnji. 



Constituent. 



Silica 



Alumina 



Iron oxide 



Calcium oxide 



Magnesium oxide __- 



Moisture (110°) 



Loss on ignition 



Sulphuric acid (SO3) 



From 

 bag. 



From 

 can. 



Per cent 



Per cent. 



19.80 



20.24 



8.33 



8.50 



2.7,i 

 63.44 



2.98 

 63.32 



2.25 



2. 1,5 



0.32 



0.14 



3.14 



2.52 



0.43 



0.42 



Tajsle VIU. — Moisture, loss on- i<jnitioii and ciirbonic acid. 



Sample No. S. 



On twenty-fourth 

 day cement from— 



Differ- 

 ence. 



Can. 



Bag. 





Per cent. 

 0.14 

 2.63 

 1.14 

 1.49 



Per cent. 

 0.40 

 3.92 

 1.64 

 2.28 



Pa- cent. 

 0.26 

 1.29 

 0..50 \ 

 0.79 



Loss oil ignition after drying 

 Carbonic arid fCOol 



Combined water 



The rapidity' with which this absorption of carbon dioxide and water 

 may take place (the local climatic conditions being those of the early dry 

 season) is shown in Table IX. 



Two dift'erent brands were investigated, and in each case 50 grams of cement 

 were taken from each of the samples specified, and put into 100 cubic centimeter 

 lieakers. These were accurately weighed and the free moisture then thoroughly 

 driven ofl' by four hours' heating at 130° C. The beakers were then allowed to 

 stand in the balance room, open to tlie aii-. but protected from dust by paper 

 coverings. The gain in weight was noted at the intervals of time designated. 

 At the end of twenty-eight and one-half days, the moisture was again di'iven olf 

 by continued heating at 130° C, and the amount of water absorbed subtracted 

 from the total ab.sorption. The samples were again reheated after thii'ty-iive 

 days' additional exposure. The results obtained in detail are as follows: 



