24 
into ball soda, and thus it is kept in constant circulation, 
instead of being lost. The loss entailed thereby is one of 
heat, and hence of fuel, in converting water into steam in 
the black ash furnace. 
In order to have some object to aim at, we commenced 
the next step by assuming the existence of such a double 
sodium calcium carbonate, as Wright believes is formed, 
under the circumstances already named ; and, as the simplest 
mode of representing such a compound, we took the liberty 
of giving it the formula 
We then made an attempt to prepare this so far hypothetical 
salt. But before proceeding to this, we will just refer to 
some experiments we made with the object of ascertaining 
with some degree of precision under what circumstances 
the insoluble sodium compound is formed. 
Solutions of caustic soda and sodium carbonate were 
prepared; the former had a specific gravity of T09 and con- 
tained 6'52 per cent Na a O ; the latter contained 5-985 per 
cent Na 2 0. 
(I.) A quantity of precipitated CaC0 3 was diffused in 
water and boiled then with 20 c.c. of standard caustic soda 
for 15 minutes. After filtering and washing till the filtrate 
was no longer alkaline, it was found by titration with 
normal hydrochloric acid that no soda had been retained by 
the calcium carbonate. 
(II.) No soda was retained either, when instead of the 
precipitated CaC0 3 , finely powdered marble was used. 
(III.) A quantity of calcium carbonate (precipitated) 
was now boiled for a long time with 20 c.c. of the sodium 
Ca 
