Intelligence and Miscellaneous Articles. 393 



which have the shield more or less depressed, and each joint of which, 

 instead of having a single partition, is closed at the two extremities. 

 On the other hand, the Bacillaria have a prismatic shield, often 

 streaked or furrowed, but without real partitions. 



M. Dujardin observes that the greater part of the tripolis in the 

 mineralogical collections of Paris by no means present this character, 

 and under the microscope only show grains of silex ; and that the same 

 is the case with regard to the silex of Saint Ouen {silex nectique), as well 

 as to the schists which envelope the menilite, which some German au- 

 thors had referred to the poller schiefer. It would seem that the tri- 

 poli or polierschiefer of Bilin, very different from the others, belongs 

 to a very recent lacustrine deposit. That of Santa Flora, which is 

 inentioned in the letter of M. Brongniart as presenting also the cha- 

 racter specified by M. Ehrenberg, seems also to be the product of a 

 deposit of recent formation, which M. Dufrenoy considers as probably 

 presenting some analogy with the siliceous deposits of the Geyser. — 

 SocUte Philomathique de Paris, July ] 6. L'lnstitut, No. 168. 



METEOROLOGICAL OBSERVATIONS MADE DURING THE SOLAR 

 ECLIPSE OF MAY 15, 1836, AT GREENWICH, BY MR. W. R. BIRT. 



h ra 



11 15 Howard's fair-weather cumulus, forming on the vapour 



plane; motion N. by E. As the masses passed over the 

 river they were seen to break into smaller patches, and 

 the thinnest dissolved. 



Observatory Vane. 



12 30 due E. The cumuli are now prevalent. 



3 N.E. Cumuli still prevalent, their motion being 



N.W. Considerable diminution of light. 

 White glare in irregular patches noticed 

 round the sun, and filling a circular space of 

 about 40° in diameter. 

 3 10 S.E. White glare more evenly dispersed ; at this 



time the wind suddenly shifted to S.E. and 

 more white glare formed in irregular 

 patches. Venus was now perceptible, and 

 continued visible for about half an hour. 

 The cumuli less numerous. 

 3 20 White glare more evenly dispersed; the cu- 



muli confined to a space of 40° round the 

 sun, except a large mass to the §.W. under 

 the sun. 

 3 30 S.E.byS. White glare still filling a space of 40°. A few- 

 masses of very thin cumuli before the sun. 

 Motion N.W. 



White glare not estimable. 



Cumulus augmenting in the S.W. 



Cumuli nearly gone. 



Breeze freshening. 



Vol. 9. No. 55. iVov. 1836. SA 



