He has only one symbol (written somewhat like a final sigma) for an unknown quantity, which he calls apc0µ6s (defined as "an undefined number of units"); the symbol may be a contraction of the initial letters ap, as A Y, K Y, D Y O, &c., are for the powers of the unknown (Suvaµcs, square; icu(30s, cube; Svva,uo& va i ccs, fourth power, &c.).
"Fehling's solution" is prepared by dissolving separately 34'639 grammes of copper sulphate, 173 grammes of Rochelle salt, and 71 grammes of caustic soda in water, mixing and making up to l000 ccs.; 10 ccs.
Water decomposes it to give hydrogen free from ammonia and acetylene, i gram yielding about loo ccs.
An approximate normal sulphuric acid is prepared from 30 ccs.
Of nitrous oxide, 67.7 ccs.