532 PHILOSOPHICAL TRANSACTIONS. [aNNO I762. 



the time that tVieir flowering stems begin to shoot ; as by that time the plants 

 will have felt the effects of the warm sun, have acquired a highly virose smell, 

 and the stems of the leaves are covered with purple spots, an argument of the ex- 

 altation of their juices : and we should be attentive hereto give them all these 

 advantages, as 3 degrees of latitude, and other circumstances of soil and situation, 

 may occasion a very sensible difference in the qualities of the same plant ; an in- 

 stance of which occurs in the plant under consideration, and may be one of the 

 causes, why the effects of the hemlock have not been such here, as we are assured 

 they are at Vienna ; viz. Dr. Storke says, that the root of hemlock, when cut into 

 slices, pours forth a milky juice, which Dr. W. had never seen it do here in 

 England. 



There are several vegetables which, though they thrive apparently well, their 

 productions are yet not the same as in other parts of the world, where the heat is 

 more intense, and the summers are of longer continuance. It would be extremely 

 difficult here, though the plants thrive very well, to produce from the white poppy, 

 or Cistus ladanifera, either the opium or the labdanum, the known production 

 of these vegetables in other parts of the world. No art can make here the tra- 

 gacantha pour forth its gum, the lentiscus its mastic, or the candleberry myrtle of 

 North America its sebaceous concrete. To these might be added many others, 

 too tedious to mention. 



In such mild winters as the last, the leaves of hemlock may be procured in any 

 part of them ; but they are not to be depended on, as their specific smell is then 

 comparatively weak, their juices poor and watery, and they are wholly without 

 spots. 



XVI. Of an AntheUon observed near Oxford, by the Rev. John Swinton, B. D. 

 of Christ-Church. Oxon. F.R.S. p. 94. 



Near the top of Shotover-hill, about 12™ past 7 o'clock in the evening, Mr. S. 

 accidentally discovered a luminous appearance, not much unlike the sun when seen 

 through clouds, about 4 or 5 times as large as the solar disk. [See fig. 1. pi. 14.] 

 The sun was then pretty resplendent, though a full exertion of its rays was some- 

 what obstructed by a thin waterish cloud. Soon after a very distinguishable 

 Mock-Sun, opposite to the true one, which he took to have been an anthelion, 

 appeared. This was not however completely formed, that part of its disk remotest 

 from the sun being indistinct and but ill defined. Nor could the figure of the 

 lucid tract round it, though approaching a circle, be with any precision ascer- 

 tained. This uncommon meteor was seated in the e, but the sun had a westerly 

 situation. From 7^ 12'" to 7^ IS*" the phenomenon shone very conspicuously, 

 though almost surrounded by dark thickish clouds. The disk of the spurious 

 sun seemed as large and bright as that of the true one, but was not so well de- 



