as a Branch of' Natural History, ^'c. 255 



Sub. Ord. IL—HYDKO-SILICIDEOUS. 



With the blowpipe in the matrass, giving water, and losing their trans- 

 parency. 



Family 1. — Hydro-Phyllidians. 



Same characters, as those of the anhydro-phyllidians, except those which 

 indicate the water of composition. 



Gtfw.— All the hydrated micas and talcs ; Cronstedtite. 



Family 2. — Triphanes. 



But feebly attacked by acids ; texture foliated ; lustre between vitreous, 

 greasy, and pearly. Spec. grav. 3, 6. Before the blowpipe fusible, with in- 

 tumescence into a colourless and transparent glass. 



Gen. — Triphane or spoduraen. 



Appendix. — Killenite. 



Family 3. — Zeolitines. 



Do not form a gelatinous mass with acids ; scratch fluor-spar ; vitreous or 

 pearly lustre. Spec. grav. 2.0 to 2.9. Fusible before the blowpipe. 

 Gen.— Chabasite ; carpholite ; harmotome, or cross-stone. 



Family 4. — Zeolites. 



(Soluble in acids, for the most part in a gelatinous mass ; texture compact 

 or thick foliated ; the harder scratch apatite, the greatest part only fluor 

 spar, some merely calcareous spar. Spec. grav. 2.0 to 3.3. Vitreous or 

 pearly lustre. With the blowpipe easily fusible with or without intumes- 

 cence. 



Gen.— Gismondine ; prehnite ; dioptase ; silicate of zinc ; datholite ; anal- 

 cime, or cubicite (Gmelenite ?) mesotype ; Thomsonite ; stilbite ; Heuland- 

 ite ; Brewsterite ; epistilbite ; apophyllite ; Laumonite. 



Appendix. — Phillipsite ; Comptonite ; Edingtonite ; Allophane ? 



Appendix to the Order Silicideous. 

 Chiastolite, or made; octohedral silicate of manganese from Piedmont 

 (Berzelius) ; Sapparite ; sidero-schistolite ; Bucklandite ; glaucolite ; thul- 

 lite ; Tumerite ; zurlite ; ostranite ? ligurite ; pyrorthite. 



Order IV.— BORIDEOUS. 



Chem. Nat. — Borates. 



Scratch feldspar ; easily soluble with the three fluxes • employed with the 

 blowpipe, into a diaphanous glass ; with a certain proportion of soda the glass 

 crystallizes ; with Turner's re-agent (a mixture of 4| parts of bisulphate of po- 

 tassa with 1 part of fluate of lime), gives a pure green colour to the flame 

 of the blowpipe. Insoluble in acids. 



Gert. — Boracite, or borate of magnesia. 



• Viz.— Borate of soda or borax ; double phosphate of soda and ammonia, or salt of phoq;»l|0' 

 rus ; and carbonate of soda, or soda. 



