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potato crop of last year are fully known, and forebodings of the worst 

 description rife, relative to the fate of the crop of the present season, 

 I trust I need make no further apology for detailing the results of a 

 series of experiments, conducted in the Botanic Garden during the 

 past winter. 



1st. On preserving potatoes. 



2nd. On the prospect of potatoes partially diseased being fit to use 

 for seed ; and, 



3rd. Whether the fungus which has appeared so uniformly on dis- 

 eased potatoes is capable of extending itself to sound tubers when 

 brought into contact with it. 



The experiments were commenced on the 29th of October last, and 

 continued to the 1st of the present month, when the results which I 

 now purpose detailing were observed to have taken place. 



With a view of ascertaining what effect the drying process would 

 produce, we selected four tubers partially diseased, and one sound, 

 which were steeped an hour in water mixed with fresh lime, and then 

 put into a large flower-pot, on the cool end of the flue of a stove, 

 where the temperature ranged between 55° and 56° of Fahrenheit. 

 The diseased tubers soon collapsed, and produced fungi in the course 

 of three weeks, after which they continued to dry up into a hardened 

 mass. The sound tuber remained quite fresh, and was not infected 

 with the fungus, although the others were placed over and under it. 



An equal number of tubers, in the same state, were subjected to si- 

 milar treatment, after being dusted with fresh lime, which appeared 

 to produce no different effect. The diseased potatoes shrivelled up, 

 and decayed quite as soon as those which were neither steeped nor 

 dusted. 



In these experiments, I would beg to observe, that the tubers were 

 exposed to the light, and not covered with any kind of mould ; but 

 duplicates of the several lots were treated in a similar manner, when 

 covered with earth, which had only the effect of keeping them longer 

 from shrivelling. The diseased tubers decayed, and left the sound 

 ones without being infected as before. 



A large garden potful, about one half sound and the other half dis- 

 eased, as they were dug out of the earth, afforded similar results. 



We next tried them on the shelves of a seed-room, where they were 

 circumstanced in some degree similar to being placed on lofts. Four 

 diseased and two sound tubers were put together,, after being steeped 

 an hour in lime and water; two of the diseased dried up into a hard- 

 ened mass, two partially so, but were putting out strong buds. Those 



