52 Dr. Heddle on MesoUte and I'aroelite {Mesole). 



The analyses bj' Berzelius, V. Fuchs, aud Geblen, agree ad- 

 mirably with this formula. 



(CaO, NaO)Si03 + A12 03, SiO^ + SIiO has been given: the 

 per-centages of this are, — 



2503-41 

 The only analysis which comes near this is that by Friesmuth 

 from Hauenstein. Rose (in his Krystallo-chemische Mineral- 

 system, p. 39) gives the mineral from that locality this formula, 

 and calls it mesolite. Dana, again, makes it mesole, with an 

 equibasic formula, with which it seems indeed best to agree (see 

 note to Faroelite). Hausmann, however [Handbuch, p. 801), 

 remarks, " der sogenannte Mesolith von Hauenstein ist nach 

 Haidinger mit Comptonit uberzogener Zeolith." And this 

 opinion, grounded probably on inspection, would seem to be 

 confirmed by a chemical consideration of the subject, as an ad- 

 mixture of Comptonite with natrolite would result in some such 

 compound; the former furnishing the lime, diminishing the 

 quantity of silica and soda, and slightly increasing that of the 

 alumina and water of the last-mentioned mineral. 



2. From Storr in Skye; colour white, in delicate feathery 

 tufts (powdered mineral absorbs "574 per cent, of moisture). 



On 25 grs. 



Silica 46-724 



Alumina .... 26-698 



Lime 8-902 



Soda 5-404 



Water 12-925 



100-653 



3. At Kilmore in Skye, mesolite occurs in yellowish-white 

 radiated crystals, forming solid masses, very different in appear- 

 ance from the specimens at the above localities, and having much 

 resemblance to natrolite. 



On 25 grs. 



Silica 46-26 



Alumina .... 26-48 



Lime 1000 



Soda 4-98 



Water 13-04 



100-76 



