GAUGING. 



A TABLE of the Segment of a Circle, whose Area is Unity. 



By such simple means we may ascer- 

 tain the dimensions of most vessels in 

 common use ; we may, indeed, ordinarily 

 estimate the diameters of casks to be in 

 the proportion of 7 at the chimb for 10 at 

 the bung, which gives a medium of 8.5. 



But gaugers are, in general, provided 

 with a neat, compact instrument, in form 

 of a folding rule, whereby the measure- 

 ment of a cask's interior may be taken 

 with sufficient accuracy. This instrument 

 consists of four pieces, each a foot long 

 and about three-eighths of an inch square. 

 It has three brass joints, for the purpose 

 of folding. On one face is a double line of 

 diagonals, one appropriated to wine, the 

 other to beer measure. By inserting the 

 lower end of the rod at the bung of the 

 cask, and directing it obliquely so as to 

 touch the junction of the head and stave, 

 and noting the figures which stand oppo- 

 site the centre of the interior of the 

 bung-hole, the measurement is taken : in 

 this process care must be taken to mea- 

 sure towards both chimbs, because a cask 

 has not always the bung truly centrical : 



when any difference appears, the medium 

 of the two measurements serves as a 

 standard. Open vessels maybe measured 

 in the same way, by measuring the ob- 

 lique line from the surface, or one side 

 to the bottom of the other side ; but only 

 half the quantity shewn on the scale is to 

 be taken for the contents. There is also 

 a scale for cylindrical vessels, which 

 shews the contents of one inch deep in 

 any given area or diameter. 



We must remark, that complete accu- 

 racy is not to be expected from this rod, 

 however justly it may have been gradu- 

 ated : because the curves of staves, as has 

 been shewn, vary so much, as to render 

 some exclusive attention to that circum- 

 stance absolutely necessary ; it being a 

 point which cannot be determined by the 

 rod or rule. The guagers in excise offi- 

 ces usually understand, at sight, if any 

 unusual curve exists, and fail not to make 

 allowance for such anomalies. The wine 

 merchants, however, for many years, got 

 the start of them, by causing the staves 

 to be hollowed out considerably, indeed 



