184 Miscellanies. 



free sulphuric acid, sulphur, and even an appreciable amount of sul- 

 phate of magnesia are also met with. 



The fossil impressions in these beds are beautifully distinct, and 

 appertain to all the species of shells which are found in perfect condi- 

 tion in the subjacent strata. In the blue clayey marl beneath, there 

 often occurs a notable proportion of green sand, which is also found 

 in some of the other Miocene strata, mixed pretty largely with com- 

 mon sand and clay, in beds destitute of fossils. 



The paper treats in detail of many of the more interesting localities 

 in the Miocene district, describing the stratification, and presenting 

 evidence of the relative fertilizing agency of the several beds. 



The fossil species which characterize the Miocene strata, are next 

 enumerated. 



In the next section, an account is given of the arrangement and 

 composition of the Eocene strata of the peninsula. 



In general, the lowest bed of the series is a dark greenish-blue 

 mass, composed of clay, fine sand, and a little green sand; while 

 above it, the strata are of various shades, yellow, greenish-gray, and 

 brown. Little uniformity prevails in their arrangement at different 

 localities. 



A thin band of feri'uginous gravel frequently overlies the Eocene 

 strata, and forms a distinct line of demarkation between them and the 

 bottom of the Miocene. 



The stratification of the Eocene at various localities is exhibited in 

 detail, and the characteristic fossils specified, while the curious chem- 

 ical changes which these have undergone, are also discussed. 



Dr. Hays stated that he had received through a friend some of the 

 vaccine virus, recently obtained by Mr. Estlin, of Bristol, from the 

 cow, and had used it with the most satisfactory results. He exhibited 

 a scab, which presented all the characters described by Jenner, as 

 appertaining to the genuine vaccine scab. 



April 19, 1839. — The Committee of Publication, reported the pub- 

 lication of Part Second, Vol. VI, of the Society's Transactions. 



Professor Bache communicated at the request of the Committee on 

 the Observatory, the following translation of a letter addressed to 

 him by Professor Encke, Director of the Observatory of Berlin. 



The nature of the operations of an observatory must depend more 

 upon the individual taste and qualifications of the director than those 

 of any other scientific establishment. There is still so much to be 

 done in every department of Astronomy, in any one of which there 

 is suflicient employment, that if a director shows a particular dispo- 

 sition for certain lines of research, it would be most profitable for 

 science that he should be allowed to follow them, and not be tied 



