l'2i PHILOSOPHICAL TRANSACTIONS. [aNNO 1764. 



communicated both to water and rectified spirit by the Vienna extract, th^t the 

 hemlock had been g^athered too soon, and before the plant was in vigour. 



Exper. 3. — The spirituous tincture of the Lisbon extract was not so green, 

 nor was the green so durable as that of the Vienna extract: the phenomena, in 

 consequence of the other experiments, did not differ materially from those of the 

 Vienna extract. 



Exper. 4. — The spirituous tincture of the extract of hemlock prepared at the 

 Apothecaries' Hall, was like in colour to that of Coimbra, but the residuum did 

 not differ considerably from that of Vienna and Lisbon. This extract has been 

 used with some success at the Westminster Hospital. 



Exper. 5. — The spirituous tincture of the powdered leaves of hemlock was 

 like in colour to the last; the residuum differed materially from that of the former 

 extracts only in its resin being considerably more fluid. 



These experiments show, that the extract of hemlock prepared at Coimbra 

 contains a far greater quantity of an essential oily salt and resin, than the other 

 extract. As the oils, salts and resins are the most active parts of vegetables, 

 may not the well-attested salutary effects of the Coimbra extract be owing to its 

 greater quantity of these active principles, particularly if we consider the large 

 dose it has been prescribed in? As these active oily salts and resins are soluble 

 in spirit of wine, we have the means of obtaining them from the extract of our 

 own hemlock in sufficient quantities for use, and without fatiguing the stomach 

 with the nauseous inactive parts of the extract. But as experience alone can 

 show whether the virtues of the hemlock reside in the whole extract, or in the 

 saponaceous parts soluble in spirit of wine, he contents himself with proposing 

 these few hints, until experiments shall enable him to lay the other consequences 

 of these assays with proper weight before the Society. 



XXXIII. On the Use of the Ganglions of the Nerves. By James Johnstone, 



M.D. p. 177. : 



This original and ingenious essay may be consulted in an enlarged form, in 

 this author's collected works, published under the title of Medical Essays and 

 Observations, 1795- 



XXXIV. Of several Fiery Meteors seen in North America. By John Win- 



thorp, Esq. at Cambridge, in New England, p. 185. 



On June 3, 1730, as Mr. W. was walking over the common in this town 

 (Cambridge) about 10 o'clock in the evening, the moon, which was newly past 

 the first quarter, shining bright, and but few clouds to be seen, he was on a 

 sudden surprised with 4 or 5 flashes of light, succeeding each other as quick as 



