[ *9 ] 
in the middle with the aluminous rain Water, and 
fwims on the top in the fimple rain water. The herb 
is turned purple, by infulion, in the Somerlham 
water; is of a yellow green in the rain water with 
allum ; and remains of a bright green when infufed 
in rain water alone. 
Experiment XX. 
The fediments, by evaporation, from Somerlham 
water differ, as is faid, of the fpontaneous feparation, 
in Experiment 1 3. according to the feafons, both as 
to color and quantity. Four pounds of the Somerlham 
water have, by evaporation, yielded in a dry feal'on, 
lixteen, or at moll twenty grains of a rulty colored, 
or orange colored fediment; whereas, after rainy 
weather, two pounds of the fame water have yielded 
one dram of a dark olive brown fediment. 
Experiment XXI. 
I put two drams of the yellow ochry fediment into 
a crucible, covered with a tile, and having calcined 
it in an open fire, it had loft a fixth part of its 
weight ; the refiduum appeared of a red rufty color, 
mixed with a white earth ; and on the fides of the 
crucible a fmall quantity of greyilh powder flicking 
to it. The red powder was partly attracted by the 
magnet. 
Experiment XXII. 
I put, at the fame time, into another crucible, a lump 
of the blue clay, brought from the Somerlham Spa, 
I) 2 weicrhin^ 
O 
