90 NOTES ON FULGURITES. 



The cause of this frequent strikiug of liglituing in similar situations 

 lias been discussed by Dr. Fiedler and others in the papers noted below. 



Supplementary note. — Since the above was written we have re- 

 ceived from Mr. S. T. Walker, Milton, Florida, two fragments of ful- 

 gurite from that place. These are each some G5""" in length by 10'"'" in 

 greatest diameter, being both somewhat flattened. Exteriorly they re- 

 semble those from Sumter, South Carolina, lacking the deep corruga- 

 tions or wings, but being very rough and scoriaceous. The color varies 

 from gray to dull ferruginous red, while the glassy lining, which in some 

 places is 5""" in thickness, is a dull lusterless black. Tender the micro- 

 scope this lining displays the properties of a true glass beautifully 

 streaked with deep smoky brown. The many stean cavities show no 

 definite order of arrangement, though the smaller ones are often grouped 

 in dense aggregates, while the larger ones, often 1"'"' across, are usually 

 single. These show a peculiar corona of brownish streaks and clouds as 

 if the coloring matter had been suddenly injected into the glass by the 

 development and bursting of the bubble. The glass, with the exception 

 of a few very minute faintly polarizing specks, is entirely black between 

 crossed nicols and shows no colors such as might be produced by stain 

 or partial crystallization. 



The following is the bibliography of fulgurites so far as I have been 

 able to gather it from available literature : 



Withering, William. [On Fulgurites.] 



Trans. Philos. Soc. Lond., 1790, p. 29.3. 



Gives an account of t lie fusion of quartz pebbles by lightning at Aylesford, 

 England. 

 Fiedler, Dr. K. G. 



Ueber BlitzriJhren nnd ilire Entstebung. Ann. der Physik, vol. 55, 1817, ji. 121- 

 104. With two plates. 



(Eiu Nachtrag zu seineni Aufsatze iiber BlitzriJhren in dieser Annalen J. 1817, S. 

 2, od. B, 55, S 121). Ihid., pp. 235 to 248, and one plate. 



Gives a very full account of the occurrence and descrijiMon of fulgurites at 

 Senner Heide, Nietleben, bei Halle, Drigg, and Aylesford, England. Discusses their 

 origin and composition. 



Gives an account of fulgurites found at Rheiue, and further discusses their ori- 

 gin. Mentions also the finding of fulgurites on the sand hills near Blanbenburg, 

 in the Harz, and near Bahia, in Brazil. 

 Gilbert, Dr. L. 



Noch einiges von den Blitzruhren. Ann. der Physik, vol. (!1, 1819, pp. 249-262. 



Gives a history of tlie finding of fulguiitcs by Pastor Hermann at Massel in 

 Silesia, in ITOG and 1707. Credits Hentzen -with having Hrst pointed out 1 heir 

 probable origin, and Fiedhir with having lirst proven this in a satisfactory man- 

 ner.- Also furtlier describes the fulgurites from Bahia, Brazil, already noted hy 

 Fiedler, and makes remarks on their origin. Describes also the. fulgurites found on 

 elevated peaks of the Mexican Cordilleras by Humboldt. 



Nachtrag zu dem Aufsatze von den Blitzrohren, S. 262. /?)/(/., pp. 315, 316. 



Brief note <ni the Mexican fulgurites before mentioned. 



Sur des tubes vitreux cpii paraissent produits par descoujis de fond re. Ann. de 

 chimie. et de physique, vol. x.xi, 1821, pp. 290-303. 



A r^snun^. of the subject up to 1821. Compiled mainly from the papers of Fied- 

 ler and Gilbert. 



