42 Dr. Burnett's Account of the Effect of Mercurial Vapours 



geminispina. M. columnaris ; mammis exiguis numerosissimis, 

 5. spinis parvis intertextis albis ; duabus in singulo fas- 

 ciculo ceeteris multoties longioribus. 



Obs. Plantae plus quam semipedales fere omnino sim- 

 plices teretes, superne sensim crassiores apice vix con- 

 vexo. Mammcc pallide virides spinis recurvo-radianti- 

 bus capillaceis albis ; duabus in singulo fasciculo valid i- 

 oribus geminatim semierectis pungentibus apice nigris. 



Obs. Spinarum fasciculi radiantes et inter se con- 

 fertim patentes, fere totam plantain eleganter tegentes. 



IX. An Account of the Effect of Mercurial Vapours on the 

 Crexo of His Majesty's Ship Triumph in the Year 1810. By 

 William Burnett, M.D.^one of the Medical Commissioners 

 of the Navy, formerly Physician and Inspector of Hospitals 

 to the Mediterranean Fleet. Communicated by Matthew 

 Baillie, M.D. F.R.S* 



TT has long been known, that in the vacuum of the barome- 

 ■*■ ter, mercury rises in a vaporous state at the usual tem- 

 perature of this climate, and that persons employed in the 

 mines from whence this metal is procured, as well as those 

 who are employed in gilding and plating, have suffered para- 

 lytic and other constitutional affections, from inhaling the air 

 saturated with mercurial vapours : had any doubt remained of 

 mercury existing in the state alluded to, it would be effectually 

 removed by the experiments made by Mr. Faraday, detailed 

 in the twentieth number of the Journal of Science, &c. 



An unprecedented event, which occurred in one of His 

 Majesty's ships of the line, at Cadiz, in the year 1810, a short 

 time before I took upon me the charge of the Medical De- 

 partment of the Mediterranean Fleet, has afforded me an op- 

 portunity of illustrating this subject on a very extensive scale, 

 the details of which may not, perhaps, be uninteresting to the 

 Royal Society. 



The Triumph, of 74 guns, arrived in the harbour of Cadiz 

 in the month of February 1810; and in the following March 

 a Spanish vessel, laden with quicksilver for the mines in South 

 America, having been driven on shore in a gale of wind and 

 wrecked under the batteries, then in possession of the French, 

 the boats of this ship were sent to her assistance, by which 

 means, during many successive nights, about one hundred 

 and thirty tons of the quicksilver were saved and. carried on 



* From the Philosophical Transactions for 1853, Part II. 



board 



