424 A, B. Lyons — Comjposition of Hawaiian Soils. 



Punahou soil already spoken of has been derived. It is what 

 is familiarly known in Honolulu as " black sand," used as a 

 dressing for driveways and garden walks. It consists of a 

 black, fresh-looking lava in irregular angular fragments, from 

 one to ten or even twenty millimeters in their several dimen- 

 Spring water that has leached through this black sand 



sions. 



Table II. Analyses of Hawaiian Lavas. 





1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 







•as 

 >3^ 







Is 

 11 



•S 



11 

 lis 



3 . 



is 



111 



0" 



>> 



00 fl 



£53 



Is 







11- 



fe - a 



m 



m 



Ml 



Av. 

















11 



WW 







1 = 

 II 



i 



11 



i 

 II 



li 





Si02 



35-86 



36^85 



58-06 



47-33 



4901 



46 30 



51-63 



49-88 



45^79 



47-86 



TiO.2 



2-90 



4-05 



1-88 



4-84 



3-93 



5-35 



2-47 



3-97 



3-25 



^•63 



AlaOs 



1210 



11-97 



18-21 



17^96 



16-29 



17-95 



12^10 



13-79 



15.09 



15-05 



FesOg 



7-82 



13-90 



4-87 



12^64 



7-61 



6-21 



8-67 



9-65 



5^34 



8-59 



FeO 



8-09 



6-54 



201 



•51 



4-89 



6-79 



3-10 



2-61 



5^58 



4^46 



MnO 



•39 



1-13 



•36 



•64 



•27 



•26 



•30 



•67 



•49 



-50 



CaO 



12-08 



9-00 



3-29 



6-29 



9^79 



8-17 



9^17 



9-59 



10-21 



8-62 



MgO 



9-72 



10-73 



1-59 



3-97 



3^62 



3-67 



9-40 



6^12 



5-92 



6-08 



Na.O 



6-23 



4-13 



6-12 



3-67 



3-82 



3-92 



3 10 



3-30 



3^67 



4-22 



K2O 



1-93 



•79 



2-75 



1-10 



•80 



•89 



•30 



•17 



•90 



]-07 



CuO 



•25 



•10 



-10 



•15 



•10 



•17 



•48 



•14 



•18 



•19 



P2O5 



1-08 



1-25 



•65 



1.05 



•49 



•53 



•26 



•26 



•29 



•65 



SO3 



•27 



tr. 



•05 



•07 



•20 



•06 



•07 



•09 



2-^4.% 



•10 



S 



FeS 

 1-40 



•14 



CoO 



-04 



-05 



•07 



•02 



•05 



•03 

 CraOg 

 tr. 



•02 

 CraOa 

 tr. 





•11 



Total 



100-12 



100-62 



99-99 



100-29 



100-84 



100^32 



101-08 



100-26 



99^25 





Dried* at 























100°, c. 





5-48 



•53 



2-38 



•98 



1-75 



•47 



1-84 







Ignited f 





4-74 



•83 



3^08 



1^00 



2-00 



•33 



M4 







* Percentage loss of original air dried powder, 



■f Additional percentage loss of original powder on ignition. 



X Derived from exposure to sulphurous fumes, and hence not considered in the averaging. 



is charged with sodium carbonate. Acids act very vigorously 

 on the sand, generating much heat and rapidly disintegrating 

 the mineral, with separation of gelatinous silica and evolution 

 of hydrogen sulphide. The lava is evidently an exceedingly 

 basic one, and it is to be observed that it comes from the most 



