358 fAsSEMfiLY 



single week's rain will rot on the tree Such also is the case of 

 other fruits. It is well known that grapes, gooseberries, currants, 

 melons, &c., often prove a failure. Indeed, it would be difficult to 

 name any production of the earth that yields full and perfect crops 

 annually: on the contrary it is well known that famine has been of 

 frequent occurrence in populous countries, through short or defective 

 crops of the necessaries of life. 



Why, then, I would ask, should we expect good potato crops twice 

 in every year? Having devoted much attention to the nature of 

 plants in general, I have come to the conclusion that the alleged 

 disease in this esculent, is not caused by defective seed, but that it 

 is generally the effect of variableness of weather, and one extreme 

 of temperature suddenly following another. In some instances, the 

 defect may have been occasioned by the injudicious use of acid ma- 

 nure, which is destructive to all description cf esculent plants in hot 

 dry weather. New land without manure, generally produces the best 

 crops in dry seasons: it must however be acknowledged, that the 

 extremes of heat, cold and moisture, are alike detrimental to vege- 

 tation in all seasons, and that hot dry summers are often attended 

 with results as fatal to vegetable productions, as the coldness of 

 winter." 



First: " The alleged disease is not caused by defective seed." 

 Mr. Bridgman certainly would not recommend the planting of defec- 

 tive seed at any time. If the defect is only a common rot, such as 

 the root has always been subject to in certain seasons, or the want 

 of proper care in gathering and housing it, it would be less likely to 

 germinate and grow healthily, than if planted in a sound state. 

 Such a defect existing during the prevalence of the rot in question, 

 would be much more hazardous, as it would be more likely to run 

 into and become the contagious rot. This is natural both as respects 

 animals and plants, when contagions prevail. 



At any rate it is a defect, the plant is made worse by it; and rot- 

 tenness (he says,) " is the effect of deterioration, produced by the ab- 

 sence of a living principle," and according to reason in such a state, 

 it would be less likely to live much more to prosper, under " the 

 absence of a living principle," than if possessing all the vital pow- 

 ers. Besides this disease lays dormant in the root, often for months 

 before it appears; when on the surface all is fair and smooth, not a 

 suspicious speck to be seen; it shows itself sometimes about mid- 

 winter, or not till spring near the planting time, and frequently does 

 great mischief at these periods. 



