23 



Dr. Kneeland presented in behalf of Mr. Charles Girard 

 a paper containing a historical sketch of Gordiacece, with 

 the request that it might be printed in the Society's Journal. 

 Referred to the Publishing Committee. 



Dr. A. A. Hayes laid upon the table one of the unique 

 specimens of crystallized Quartz, containing acicular crys- 

 tals of Rutile, from Waterbury, Vermont, presented to 

 the Cabinet of the Society by Edward E. Phelps, M. D., 

 member of the Society, residing at Windsor, Vermont. 



This specimen was early obtained for the Society by Dr. 

 Phelps. It presented some points of chemical interest, and 

 Dr. Hayes was requested to examine some of the minerals 

 accompanying it. These have unfortunately been lost or mis- 

 laid. They consisted of hair-shaped crystals of Rutile, exfoliated 

 mica, with bisulphuret of iron and tabular fragments of quartz. 

 The latter had impressions of the Rutile crystals, and were 

 evidently the fractured remains of other crystals produced by 

 inequalities of expansion. 



A careful examination of this crystal has led to the conclu- 

 sion, that it was formed in a cavity containing the needle- 

 formed crystals already implanted on its surfaces. In the dif- 

 ferent positions of the planes of the quartz crystal, these crystals 

 are seen broken and somewhat confused, but they often present 

 regular terminations and pass through and roughen the surfaces 

 of the quartz. 



The most interesting fact, however, in connection with the 

 disposition of the minute crystals is, the entire absence of any 

 indication of 'polarization. Most commonly, when intrusive 

 matter is found in the large quantity here shown, it becomes 

 polarized with the matter of the crystal in which it occurs, and 

 without altering its general form, enters mechanically into its 

 composition. In this case the polarizing power has not acted 

 on the Rutile crystals, to dispose them in lines, or nodal points ; 

 they appear simply as a mechanical mixture. 



The numerous flaws and rents in the mass of the crystal 

 appearing most frequently where the Rutile crystals are most 

 abundant, indicate that these crystals, by changes of tempera- 



