BY FRITZ NOETLING, M.A., PH.D., ETC. 9I 



10. Grey Hornstone, Mona Yale 2.681 



11. Dark Blue Hornstone, Mona Vale 2.701 



12. Grey Streaky Hornstone, Melton Mowbray 2.701 



13. Blue Hornstone, Johnstone's Quarry, Mel- 



ton Mowbray 2.703 



14. Grey Streaky Hornstone, Melton Mowbray 2.735 



15. Blue Hornstone, Johnstone's Quarry, Mel- 



ton Mowbray 2.746 



16. Blue Hornstone, Mona Vale 2.750 



17. Blue Hornstone, Johnstone's Quarry, Mel- 



ton Mowbray 2.761 



18. Grey Hornstone, Nichols' Quarry, Melton 



Mowbray 2.780 



19. Lig'ht Grey Hornstone, Mona Vale 2.847 



The above figures prove at once that the Tasm'anian 

 Hornstone is rather a heavy rock ; the average specific 

 gravity being 2.687, it will be seen that only two speci- 

 mens are under 2.600, while all the others are well above 

 this. The figures for specimens obtained directly from 

 the quarry are rather interesting. They are for : — 



Hutchison's Quarry, Syndal — a very dark blue horn- 

 stone — 



(3) 2.610. 

 (5) 2.631. 

 Johnstone's Quarry, Coal Hill, Alelton Mowbray — ■ 

 a dark blue hornstone — 

 (13) 2.703. 

 (15) 5.746. 



(17) 2.761. 



Nichols' Quarry, Melton Mowbray — a grey horn- 

 stone — 



(18) 2.780. 



These figures seem to indicate that the hornstone 

 from different places varies somewhat, and that, strange 

 to say, the light grey variety is the heaviest of all, while 

 the dark blue stone found in Hutchison's quarry is, con- 

 trary to expectations, the lightest of all. On the other 

 hand, the figures for one and the same locality vary, 

 and I am afraid that, however tempting it may be to 

 ascertain the locality from wliich a certain implement 

 came by means of the spec, gravity, it is impossible to 

 do this for the present. 



