376 PHILOSOPHICAL TRANSACTIONS. [aNNO 1739- 



be referred to the increased diameters of the moon and star; for if the lunar 

 atmosphere were the cause of this appearance, it would always be observed the 

 same in all stars, and in any apertures of objectives. Besides, there has not as 

 yet been observed the progression of any star in the moon's disk, unless it be 

 of the first, or perhaps of the second magnitude, and that by only the half of 

 it at most, and it is well known, that their whole diameter is insensible, and is 

 only increased by spurious rays; whence the adventitious rays, both of the 

 moon and star, are mixed in the bottom of the eye, before the true conjunc- 

 tion of their bodies; and if the visible limb of the moon were the limit of the 

 atmosphere and not of the body, no mountains would be observed on its peri- 

 phery with the larger tubes and narrower objective apertures ; which, however, 

 as beforesaid, are seen plainly enough. 



From all these then it is manifest, that the moon is not surrounded with a 

 refracting atmosphere, or one capable of being observed; though there might 

 be one producing a horizontal refraction of l" or 2"; and this seems to be coun- 

 tenanced by the larger spots in the moon, which cannot by any means be taken 

 for woods, as Hartsocker and some others have imagined; for the shadows of 

 the edges are always observed nearer to the bright limb of the moon ; whence it 

 is rightly concluded that they are cavities, and not woods, as these would pro- 

 ject a shadow from the other side. Further, some fluid may well be supposed 

 to be in them; in which case it would be very agreeable to philosophy, that 

 they should emit some vapours, the congeries of which would represent a kind 

 of atmosphere ; which would not be found very dense, since, by Sir I. Newton's 

 demonstrations, it could hardly equal a third of that of the terrestrial vapours, 

 nor be observed alike at different times, those vapours being destitute of any 

 other addition. 



^n extraordinary sinking down and sliding away of some Ground at Pardines 



near Auvergne. By M. T. Communicated by Phil, Henry Zollman, 



- Esq. F. R. S. N° 455, p. -ITI. 



The village called Pardines, was composed of 46 buildings ; the ground on 

 which it was built, as well as that of the whole hill, is a good and light earth, 

 mixed with a little white clay; there are also in it some stones and rocks of a 

 middling size. This land was very well cultivated, and very fruitful, consisting 

 of fields sowed with corn, of orchards, but for the most part of vineyards; the 

 whole ground was overspread with fruit-trees, particularly walnut-trees. This 

 earth used to dry soon, and chap froii) the heat; some clefts of a considerable 

 depth, which growing wider and wider, often formed several gullies. 



