134 THIil PROGRESS OF GEOLOGICAL RKSEARCH IN TASMANIA, 



as state Mining Engineer, had several fragments presented 

 to him by one of his prospectors. These fragments were re- 

 ported to have been derived from the Western portion of the 

 Jukes-Darwin area, and the assignment of the writer to carry 

 out a geological survey of that area early in 1913 gave an ex- 

 cellent opportunity for a detailed investigation of the oc- 

 currence. The results of such investigation are presented 

 in Record No. 3 of the Geological Survey, and the conclusion 

 there indicated that this substance is of cosmic origin and 

 belongs to the Tektites, being most nearly allied to the Mol- 

 davites, but differing from the latter in the remarkably 

 high silica content (89 per cent.). Since the publication 

 of that official description Dr. H. S. Summers has discussed 

 the composition in relation to the other members of the 

 Tektites, and Dr. F. Suess, of Vienna, the world's authority 

 on this subject, has fully discussed this substance and its 

 bearing on the whole problem of the Tektites in a paper 

 entitled "Ruckshau und Veneres uber die Tektitfrage."(3) 

 The writer would, however, here enter an objection to 

 the name proposed by Suess, namely, ''Queenstownite," on 

 the grounds that the Darwin Glass does not occur at Queens- 

 town, the nearest occurrence being ten miles from that town. 



VII. MINERALOGY. 



Considerable advance has been made in this branch of 

 geologic science during the period under review. Most of 

 the increase in knowledge has been gained during the pet- 

 rographic researches indicated in the preceding chapter, and 

 also incidentally to the intensive study of our ore-deposits, 

 which will be dealt with in the chapter following this. 



It is to the late W. F. Petterd that the greatest amount 

 of credit must be given for our advance in our knowledge 

 of the minerals of Tasmania. The "Catalogue of the Miner- 

 "als of Tasmania," published by that enthusiastic mineralo- 

 gist in 1896, was a valuable contribution, and served as the 

 standard reference on Tasmanian Mineralogy until 1910, by 

 which time the increased information acquired necessitated 

 its re-writing, which was completed early in that year and 

 publii^ed under the authority of the Mines Department. 

 The advance made in that period is well indicated by the 

 fact that this second edition contains descriptions of over 

 one hundred more mineral species than the first compilation. 



(3) Mitteil der Geol. Sesell. Wien. L, ii., 1914. 



