166 University Geological Survey of Kansas. 
These constituents are probably combined as follows: 
No. 1. INO) No. 3. No. 4. No. 5. No. 6. 
Silica and insoluble residue ... 9.7 ORS 40 lO lO RS Aan i omecs UL CS 
Tron and aluminum oxides .... 0.30 0.50 0.44 0.42 1. 0.67 
Magnesium carbonate ........ 0.70 11 (0), 983 0.82 2.00 0.93 
@alciumycarhbonates eae Onl ar || TE BS) | UO 0) | Deb Tis) A: 
Calciumepsuliphatetee eee 64.91 | 69.06 | 68.36 | 59.84 | 39.08 69.60 
Wi CST Resear y tal Re) rae A Renney NO BO 9.02 Ab Ns) | 1G.8 4.18 4.78 
RO Gall Spaeth a sees ies coe yes 99.18 | 99.89 | 101.12 | 98.77 | 96.76 99.35 
An examination of the second and third columns shows that 
1.06 per cent. of water was driven off during the first two 
hours, and the remainder, 1.28, during the remaining time.. 
This is about what would be expected, when it is remembered 
that some time is necessary to get the mass to a sufficiently 
high temperature so that the water begins to be eliminated 
rapidly. The remarks that were made in reference to the de- 
hydration apply also here. If the theoretical amount of water 
in each sample is compared with the actual amount found, the 
results are as follows: 
No. I. No. 8. No. 4. No. 5. No. 6. 
Mincoreticalerromy Cas Ofer aaee 17.67 | =4.52' | 16.29 
2.58 4.60 
Wiatterclouirrels ese ane eee eames an tea WA B30 4.98 | 16.35 4.18 4.78 
ah HE) TERT TA COM tc ae entie ener Ny cB He EB 0.30 0.46 0.06 1.60 0.18 
There seems to be an excellent agreement in all cases except 
in the screenings. ‘The difference in the case of the screenings 
was greatest in the other set of analyses. This is probably due 
to the fact that we have here other material present in so large 
a quantity that our supposition in regard to the combination of 
bases and acids is not correct. 
The sample containing retarder should be compared with 
No. 3, and there seems to be a fair agreement here also. The 
quantity of the retarder that is added is so small 1t has not ma- 
terially affected the composition. 
