MR. BERKELEY ON THE POTATO MURRAIN. 13 



p. 560, when it had become so prevalent in the Lsle of Wight as 

 to attract general notice and to excite great alarm. It had doubt- 

 less made its appearance some weeks previously, but probably not 

 so early as in Belgium, where it was observed about the 10th 

 of July, and on the 18th of August it had been so fully dis- 

 cussed that Dr. Morren, following the track of Dr. Van Oye and 

 Mile. Libert, published in the Belgian ' Independance ' of that 

 date a very full account, and suggested remedial measures. If 

 one of the.se had been followed generally, viz. removing at once 

 the diseased haulm, it is, I think, most probable that we should 

 have heard little more of the disease.* 



A week after Dr. Bell Salter's first notice it was pretty gene- 

 ral in the South of England, for on the 23rd of August few 

 sound samples of potatoes were to be found in Covent Garden 

 market, and Dr. Lindley had been able from personal observa- 

 tion to write the excellent article to which we shall presently 

 have occasion to advert. The first public notice taken of the 

 subject at Paris, as far as I can discover, was at the Societt^ 

 Philomathique on the 30th of August, when the subject was 

 introduced by Dr. Montagne, a few days before any commu- 

 nication had been made at the Academy. Since this period up 

 to the present time it has been the subject of constant investiga- 

 tion. 



The disease then appears to have commenced in Belgium and 

 to have radiated from thence, taking a gradual progress to the 

 north and west, when it had become established in the south. On 

 the 30th of August it was not known in the midland counties, 

 though a few days after it was very general. It commenced in 

 Ireland about the 7th of September, and somewhat later in 

 Scotland. At the end of October Dr. Bell Salter informs usf that 

 the disease was making its appearance in young plants. 



Opinions of the most contrary description have been advanced 

 respecting the cause of the disease, some attributing it entirely 

 to the peculiar season, which, granting it to have been exactly 

 such as the advocates of this notion assume, might more readily 

 be admitted were it not certain that the malady has been pre- 

 valent even to a great extent in one season at least very different 

 from that of 1845 ;| others refer it to electric influences, to 



* The evidence indeed is somewhat contradictory on this point, but pre- 

 ponderates greatly in favour of the practice. The fact that diseased tubers 

 occur sometimes before the haulm is much affected shows that it would not 

 have entirely arrested the malady. 



t Gar. Chron. 1845, p. 742. 



X Up to the 28th of September the mean temperature of 184.5 was nearly 

 three degrees below that of 1844 ; the quantity of rain during the corre- 

 sponding period of 1844 being scarcely more than half the average. 



