Natural History, 439 



the contrary which he has ohserved are formed within the vesicles ; 

 they cohere firmly in round conglomerates, and they are not of a 

 long fine filiform appearance, but true crystals, broad and short, 

 presenting in the microscope distinct faces and angles. These 

 curious observations have been made by M. Turpin on a Cereiis 

 Peruvianus which died lately in the Jardin du Roi, where it had 

 vegetated 130 years. When looking with the naked eye at the 

 cellular tissue of the pith of this old tree, he remarked that it was 

 crammed as it were with a fine brilliant white sand. A lens suf- 

 ficed to shew that each of these grains was a mass of crystals, and 

 then, on closely examining the whole by the microscope, the fol- 

 lowing facts were determined. The crystals in question were 

 white, or rather transparent, prismatic, tetragonal, rectangular, 

 terminated by a tetrahedral pyramid, which most usually was de- 

 stroyed, because of the extreme fragility of the crystals. They were 

 rarely isolated, but usually in rounded radiating groups, of which 

 the diameter was about the sixth of a millimetre (0.00656 of an inch). 

 M. Turpin then wished to observe these same crystals in the living 

 tissue, so as to ascertain their situation and origin : the cellular 

 tissure of the pith appeared to him to be composed of unequal 

 vesicles, membranous, diaphanous, round, placed irregularly one 

 on another, filled with water and air, and containing also grains of 

 green fecula ; and he assured himself that the crystals were formed 

 in the interior of the vesicles, and that the masses of green fecula 

 served as bases or nuclei for the first crystallizations. The abund- 

 ance of these crystals in the dry tissue of the present instance al- 

 lowed of a chemical analysis being made, and they were found to 

 consist of oxalate of lime. The reporters verified all these facts, 

 and express their conviction that M. Turpin's memoir adds very im- 

 portant and remarkable facts to the few previously known, relative 

 to the crystallizations which occasionally form in the interior of 

 plants. — Revue Ency. xlv. 765. 



11. Russ:lan Diamond Mines. — When in the year 1826, Professor 

 Engelhardt undertook a scientific journey into the Uralian Moun- 

 tains, he remarked that the sands in the neighbourhood of Koushra, 

 and those of the platina mines at Nigny-Toura, strikingly resembled 

 the Brazilian sands in which diamonds are found. Baron Hum- 

 boldt, during his late residence in the samr country, confirmed this 

 resemblance ; and examinations having been made according to his 

 advice, a young countryman who was employed in washing the auri- 

 ferous sand, on the grounds of the Countess Polier, discovered a 

 diamond on the 20th of June last, which was in nothing inferior to 

 those of Brazil ; soon after, many others were found superior in 

 weight to the first. Thus Russia has added this source of riches to 

 those which of late years it has obtained in the form of gold and 

 platina mines from the Ural chain of mountains. — Revue Encyc. 

 xlv. 460. 



