372 



2. On the Quarantine- Classification of Substances, with a 

 View to the Prevention of Plague. By John Davy, 

 M.D., F.R.S., L. & E. 



In this paper, the author, after having noticed the ordinary quar- 

 antine classification of substances, into susceptible, non-susceptible, 

 and doubtful, states as the result of his inquiries conducted in Tur- 

 key and the Mediterranean, that the distinctions involved in this 

 arrangement have been made in a vezy unsatisfactory manner, not 

 after careful research and deliberation, but rather during a period of 

 panic, and hastily, in comparatively remote and ignorant times, and 

 by men, for the then state of knowledge, ill qualified for the task, 

 even had they entered upon it with all the calmness and caution 

 that the subject required. 



He next enumerates the principal substances constituting the 

 three diff'erent classes, and then comments on each of them. His re- 

 marks tend to shew that the class of so-called non-susceptible articles, 

 as glass, wood, metal, pottery, &c., since they have not any power 

 of destroying, repelling, or preventing the adhesion of animal matter, 

 ought rather to be considered as susceptible of conveying the matter 

 of plague, in the same way that they are capable of conveying vac- 

 cine lymph, i.e., if dried, or in tubes from which air is included; 

 on the contrary, that the substances arranged in the class of so- 

 called susceptible articles, as cotton, wool, fur, feathers, &c., articles 

 abounding in atmospheric air, — the great promoter of the decom- 

 position of putrescible animal matter, — are least entitled to be held 

 fit to preserve and convey the matter of contagion, an infei-ence 

 confirmed by what is known relative to the preservation of animal 

 matter generally, and especially vaccine lymph, and further con- 

 firmed by accumulated inference in lazarettos ; according to which it 

 would appear that there is no well authenticated instance on record 

 of plague having been produced within the walls of a lazaretto, 

 amongst those persons whose duty it is to examine and expose to 

 the air the so-called susceptible articles imported from the Levant, 

 and especially cotton and silk. In commenting on the subject, the 

 author takes for granted that plague is propagated by a fixed matter 

 of contao-ion, according to the commonly received views of the con- 

 tagionists, as it is only on this ground that the quarantine system 

 itself can be supported, or any discussion of the question of- tho 

 classification of substances be called for. He points out, at the 



