l$8 



THE CHONDROMETEfc, 



After submitting these observations, I shall only remark, that 

 the nearly total disappearance of the phenomenon of the auror3 

 borealis, which has taken place from the year seventeen hun- 

 dred and ninety, to the present time, agrees with the diminution 

 of the westerly variation of the magnetic needle, which like- 

 wise commenced nearly at the same time. 



The observations contained in this notice, may be considered 

 as the commencement of a series in which those afforded by 

 future observers, will, no doubt, be mof; accurate and extended 

 than what our predecessors have left us. 



The chondro- 

 meter consists 

 of a small 

 measure for 

 com, &c. 



Method of 

 measuring, 



Description of a portable Instrument for ascertaining the 

 quantity of Grain by weight, called the Chondrometer*. 



IN plate TV. Fig. 2. A B C represents a lever or balance 

 moveable on the fulcrum B and supported by the stand G. 

 The bucket F which in the instrument before me has the 

 capacity of 8f- cubic inches, is to be rilled with grain, and when 

 taken off and the handle turned back, may have its contents 

 regulated by striking over the surface with a cylindrical straight 

 piece, of about one-seventh of the diameter of the measure. 

 The arm B C, carries a division, by means of which the sliding 

 weight E can be set to counterpoise the bucket, and its con- 

 tents at any weight of the latter between twenty-five and 

 seventy-five pounds. 



It scarcely need be observed, that the quality or product of 

 any kind of grain or flour will, under like circumstances, be 

 better the heavier its weight, and that a portable instrument to 

 ascertain this must afford more accuracy than examination 

 by hand. In the use of the present instrument very little 

 instruction is necessary. The measure is to be filled in the 

 same careful manner as a real bushel, and struck even by the- 

 rule, and not by a flat thin edge, which last would carry off too 

 much of the grain ; and rough grain such as oats or barley, 



* The instrument, from which the drawing in the plate was taken, 

 was made by Messrs. Page and Ovenden, in the Stmod. 



should 



