267 



yet fluid parts had run out, thus leaving the consolidated edges 

 around the cavity. Mr. Alger had seen something similar to 

 this formed in the same way among artificially produced crystals, 

 as for example, pure lead and lead ore partially desulphuretted, 

 where the metal flowed out after an outer crust had formed over 

 some of the faces of the crystals. The great size of this crystal, 

 and the fact that the large cavity contained oxide of iron possibly 

 derived from pyrites, had led some to regard it as a pseudo- 

 morph of sulphuret of iron. He was not disposed to ascribe any 

 such unnatural and forced origin to this beautiful production. 

 He believed it to have been formed under the ordinary circum- 

 stances of crystallization, and in a matrix so soft as to give it full 

 freedom to take its proper form. In Haiiy's time, crystals of 

 gold in the form of the cube were very rare, so much so that he 

 speaks of them with some degree of doubt, and gives no such 

 figure. Mohs says, tlierj are often hollow, while the octahedrons 

 are smooth. Beudant says the crystals are usually very small ; 

 Cleaveland says, that they are small and imperfect. Nicol, in 

 his late work on Mineralogy, says of gold crystals in general, 

 " they are small and very small." 



Mr. Alger also exhibited Cinnabar, from California. 

 He presented, in the name of Mr. George E. Tyler, three 

 bulbs of the Soap Plant, Phalangium pomeridianum, from 

 California, with the following letter, giving an account of 

 its mode of growth, &c. The thanks of the Society were 

 voted for the donation. 



The Soap Plant grows all over California on high hills as well 

 as in low vales. The leaves make their appearance about the 

 middle of November, or about six weeks after the rainy season 

 has fairly set in ; they never grow more than one foot high, and 

 the leaves and stalk drop entirely off* in May, though the bulbs 

 remain in the ground all summer without decaying. It is used 

 to wash with, in all parts of California, and, by those who know 

 its virtues, it is preferred to the best of soap. 



The method of using it is merely to strip off" the husk, dip the 

 clothes in water, and rub the bulb on them ; it makes a thick 

 lather, and smells not unlike new brown soap. 



