THE 



PHILOSOPHICAL MAGAZINE 

 AND JOURNAL. 



3P' OCTOBER 1822. 



XLIV. On the proposed Alteratioti of Weights and Measures^ 

 and the Adaptation of Gauging Apparatus thereto. JBy Wm. 



GUTTERIDGE, Esq. 



To the Editors of the Philosophical Magazine and Journal. 



A Saint Fin-barrs, Cork, Aug. 6, 1822.' 



s an advocate for the change contemplated 

 in the weights and measures of the nation, I soHcit j^our per- 

 mission to address a few observations upon the subject through 

 the medium of your Magazine. 



The theory, upon which the alterations are grounded, is as 

 follows : 



1. That an inch in length shall be ^^1%%^ P^'^''^^ of the 

 length of a pendulum, vibrating seconds in London, in a va- 

 cuum, upon a level of the sea ; nence the length of the pendu- 

 lum, from the axis of suspension to the centie of oscillation, 

 will be 39i'p%%% inches. 



2. That a grain troy shall be equal in weight to 2 jiffjr 

 parts of a cubic inch of distilled water, at 62" of temperature, 

 in air ; hence the weight of a cubic inch of such water will be 

 252J^^'\; grains. _ _ 



3. T. hatTOOO troygramsshallconstituteanavoirdupoispound. 



4. That 10 lbs. avoirdupois of such water shall fill a gallon; 

 hence the cubical capacity of the gallon will be 277x%''o% inches. 



5. A gallon of water, between 70" and 39", varies in bulk 

 rather less than ^ of a cubic inch. 



6. Clear river water exceeds distilled as I'OOOG to 1, or 

 about ^ of a cubic inch in a gallon. 



7. Taking •00001044 as a mean expansion of brass for each 

 degree of the thermometer, varies the content of a gallon, be- 

 tween 70° and 39", just } of a cubic inch. 



For the accommodation of the public, I have performed all 

 the requisite alterations upon gauging apparatus, to render 

 them exclusively applicable to the new system. Some I have 

 altogether superseded the necessity of, by introducing instru- 

 ments of my own invention, less o])erosc and more correct. 

 In poijJt of accuracy, I will just give one iusti\nce by way of 

 specimen. 



Vol. 60. No. 294. Oct. 1822. H h An 



