£30 Dr. Pearson’s Experiments and Obfervations 
by diftillation from the folution which left this mafs was found 
to be merely diluted nitrous acid. 
The refiduum left on the filter which had refilled folution in 
nitrous acid, being well dried, weighed a little more than 142 
grains. This refiduum was digefted, and boiled as before in 
nitrous acid; and this menftruum, diftilled from the refiduum, 
being evaporated to drynefs, afforded 6,5 grains of a whitilh 
mafs. The refiduum left on the filter after this fecond application 
of nitrous acid, being well dried, weighed 132 grains. 
The mafs of 129 grains, left on evaporation of the above folution 
of James’s Powder in nitrous acid, in a few hours began to deli- 
quefce, efpecially at the edges. Some of the deliquefcing part 
of the mafs was difiolved in one ounce and a half of water, 
forming an opal-coloured folution, with a white fediment. 
This opal-coloured folution being filtered was examined. 
(a) It rendered lime-water milky ; and the milkinefs did not 
difappear on adding concentrated acetous acid, but readily on 
pouring into the mixture a little acid of nitre. 
( 3 ) It turned thick and white, and foon depofited a copious 
fediment of white matter, with a few drops of nitrous folu- 
tion of mercury ; and became turbid alfo with nitrated filver. 
( c ) With muriated barytes it became very turbid, and re- 
mained fo after adding acetous acid; but grew clear again on 
adding nitrous acid. 
( d ) Acid of fugar produced a turbid appearance. 
0 CaufKc volatile alkali produced very little precipitation ; 
but a copious one took place with mild alkali of tartar; which 
precipitated matter, after decanting the clear folution, was 
nearly all diffolved by acetous acid, and the remainder was 
readily taken up by the marine as well as by the nitrous 
acid. 
(/) Prufiian 
