some Carbonates of the Calcite Group. 327 





Table III. 





Data for preparing ruler when distance from crystal to plate 





is 5 cm. 





Left side 



Eight side Left side 



Right side 



of ruler 



of ruler of ruler 



of ruler 



cm. 



cm. cm. 



cm. 



1.50 



34.06 3.60 



15.50 



1.55 



33.01 3.65 



15.33 



1.60 



32.02 3.70 



15.16 



1.65 



31.10 3.75 



14.99 



1.70 



30.24 3.80 



14.84 



1.75 



29.41 3.85 



14.69 



1.80 



28.65 3.90 



14.54 



1.85 



27.92 3.95 



14.40 



1.90 



27.23 4.00 



14.26 



1.95 



26.58 4.10 



13.98 



2.00 



25.96 4.20 



13.73 



2.05 



25.38 4.30 



13.48 



2.10 



24.82 4.40 



13.25 



2.15 



24.29 4.50 



13.02 



2.20 



23.78 4.60 



12.82 



2.25 



23.29 4.70 



12.62 



2.30 



22.84 4.80 



12.43 



2.35 



22.39 4.90 



12.25 



2.40 



21.97 5.00 



12.07 



2.45 



21.57 5.10 



11.90 



2.50 



21.18 5.20 



11.74 



2.55 



20.81 5.30 



11.59 



2.60 



20.45 5.40 



11.44 



2.65 



20.11 5.50 



11.30 



2.70 



19.78 5.60 



11.17 



2.75 



19.47 5.70 



11.04 



2.80 



19.16 5.80 



10.91 



2.85 



18.87 5.90 



10.79 



2.90 



18.58 6.00 



10.67 



2.95 



18.31 6.10 



10.56 



3.00 



18.05 6.20 



10.45 



3.05 



17.80 6.30 



10.35 



3.10 



17.55 6.40 



10.25 



3.15 



17.32 6.50 



10.15 



3.20 



17.09 6.60 



10.06 



3.25 



16.87 6.70 



9.97 



3.30 



16.65 6.80 



9.88 



3.35 



16.44 6.90 



9.80 



3.40 



16.24 7.00 



9.72 



3.45 



16.05 





3.50 



15.86 





3.55 



15.68 





