56 DISCOURSE ON THE STUDY 



security while surrounded with an atmosphere more 

 explosive than gunpowder : the life-boat, which 

 cannot be sunk, and which offers relief in circum- 

 stances of all others the most distressing to human- 

 ity, and of which a recent invention promises to 

 extend the principle to ships of the largest class : 

 the lighthouse, with the capital improvements which 

 the lenses of Brewster and Fresnel, and the elegant 

 lamp of lieutenant Drummond, have conferred, and 

 promise yet to confer by their wonderful powers, 

 the one of producing the most intense light yet 

 known, the others of conveying it undispersed to 

 great distances : the discovery of the disinfectant 

 powers of chlorine, and its application to the de- 

 struction of miasma and contagion: that of quinine, 

 the essential principle in which reside the febrifuge 

 qualities of the Peruvian bark, a discovery by which 

 posterity is yet to benefit in its full extent, but 

 which has already begun to diffuse comparative com- 

 fort and health through regions almost desolated by 

 pestiferous exhalations * ; and, if we desist, it is 

 not because the list is exhausted, but because a 

 sample, not a catalogue, is intended. 



(46.) One instance more, however, we will add, to 

 illustrate the manner in which a most familiar effect, 

 which seemed destined only to amuse children, or, 

 at best, to furnish a philosophic toy, may become a 

 safeguard of human life, and a remedy for a most 



* We have been informed by an eminent physician in Rome, 

 (Dr. Morichini) that a vast quantity of the sulphate of quinine 

 is manufactured there and consumed in the Campagna, with 

 an evident effect in mitigating the severity of the malarious 

 complaints which affect its inhabitants. 



