the Specific Gravity of Scotch Barley and Bigg. 175 
tubes are inserted in this cover, one in the top or middle, and 
one on each side, but all three level on the top, and communi* 
eating with the cylinder, or small bushel. The whole brass, in- 
cluding both cylinder and lid, weighs 7898 grains; and the 
quantity of distilled water which it contains is 6114 English 
Troy grains, at 60° of Fahrenheit; both brass and water weigh- 
ing 14012 grains. The top is then taken off*, the greater part 
of the water is poured out, and 1000 Troy grains of barley or 
Scotch bigg are mixed with the water left in the cylinder, and 
stirred for two minutes with a glass- tube, to prevent the adhesion 
of air-globules to the corn ; water being gradually poured in till 
the cylinder is nearly filled. After this, the top is put on, and 
more water is poured in, with a hollow glass tube, into one of 
the brass tubes at the side, till the water rises on the opposite 
brass tube. If there is not quite enough of water, a few 
drops are let fall into the middle tube. If there is rather too 
much, it is taken opt from that tube. The whole is then weigh- 
ed. The additional weight occasioned by the mixing of the 
barley or bigg being thus ascertained, by subtracting the first 
weight of brass and distilled water from the second weight of 
brass, water, and barley or bigg, 1000 grains are subtracted 
also from the weight of brass and water, to ascertain the weight 
of water displaced by the barley. Then 1000 grains are divided 
by the number of grains of water displaced, and the quotient Is 
the specific gravity. 
The beam used in weighing these different articles, |s a very 
fipe one made by Durward in Aberdeen, for which I paid £ 2, 
5s. The weights were brass ones, which were made by Wil- 
liam Spring, then in the employment of Messrs Gordon, Barron 
and Company, and consist of twenty-four pieces, viz. 1090, 
2000, 3000 and 4000 grains ; 100, 200, 300 and 400 grains ; 
10, 20, 30 and 40 grains; 1, 2, 3 and 4 grains; J^th, T 2 oth, 
f\th and T 4 0 thsof a grain; and T J$th, T §oth, T | 5 th and T | c ths 
pf a Troy grain *. The whole were made from an average of 32 
Troy pounds, the standard Troy weights of the City of Aberdeen, 
sent down at the Union in 1707, but not exactly aliquot parts 
* These twenty -.four pieces of metal form 1,111,100 different; weights^ 
