from the GNU version of the Collaborative International Dictionary of English
- adj. Of, pertaining to, or designating, a sulphonic acid obtained, as a blue solution, by dissolving indigo in sulphuric acid; -- formerly called also cerulic sulphuric acid, but properly called indigo-disulphonic acid.
from The Century Dictionary and Cyclopedia
- Same as sulphoindigotic.
Sorry, no etymologies found.
In making the experiment, only enough of the sulphindigotic acid must be added to give the water a decided blue color.
I will pour some more of this sulphindigotic acid (1) into a flat dish, and will then make a porous dike of sand separating the two portions of fluid into two parts (FIG. 50), and now we shall be able to see whether there is any difference in the two ends of the battery, and which it is that possesses this peculiar action.