272 G. CARR ROBINSON AND W. L. GOODWIN ON THE LEUCOLINE SERIES. 
The salts of these bases, if we except the lower members of the series, do not 
appear to crystallise. As already stated, the chloroplatinates are precipitated 
in the form of granular yellow masses, which under the microscope appear to 
consist of tufts of silky crystals, but we have hitherto completely failed to re- 
crystallise the precipitated chloroplatinate, as was effected by G. WILLIAMS 
with the platinum salt of cryptidine. 
We would suggest, that in order to distinguish these five bases from their 
isomers of the Chinoline series—Tetrahiroline, &c., they should be termed Tetra- 
coline, Pentacoline, &c., thus WILLIAMS’ bases being Leucoline, Iridoline, and 
Cryptidine, the series will now consist of— 
Leucoline, . : : C,H,N Pentacoline, . i OPN i 
Iridoline, . : C,H N Hexacoline, : C,,H,,N 
Cryptidine, . ‘ : OU Heptacoline, . ' C,,HoN 
Tetracoline, : ‘ C,.H,,N Octacoline, C,.Ho,N 
Action of Nitric Acid on these Bases. 
The study of the action of nitric acid on these five bases has not as yet 
yielded any very promising results. As was stated in an early part of this 
paper, we were led to believe from the analysis of the platinum salts prepared 
by evaporating the bases with strong nitric acid, that “ nitro-compounds” were 
formed. At two stages of the fractional distillation—at the twentieth and the 
twenty-fifth-—_platinum salts were prepared from fraction 290°-295° by dissolv- 
ing the base in strong nitric acid, evaporating the solution on water-bath, 
treating the residue with water, and from this precipitating the platinum salt 
by addition of platinum chloride ; both salts yielded 23°37 per cent. platinum, 
this corresponding with the calculated percentage of platinum in substance 
having the formula 2C,.H,,(NO,)NHCI, PtCl,, but further examination did not 
bear out this theory, for the same platinum salt yielded on combustion— 
I. Il. 
Carbon, . ” . 39°42 39°00 
Hydrogen, , : 4:5 45 
whereas the above formula requires only— 
Carbon, - ; 34:12 per cent. 
Hydrogen, . : ; BS! ti 
It is apparent also from these analyses that the chloroplatinate prepared 
with nitric acid have not the same composition as those prepared with hydro- 
chloric acid. 
