This, [then, for them -] so let them taste it: burning despair and ice-cold darkness

Yea, such! - then shall they taste it,- a boiling fluid, and a fluid dark, murky, intensely cold!-

Here is a boiling and an ice-cold draught, so let them taste it,

This -- so let them taste it, boiling and intensely cold (drink),

This - so let them taste it - is scalding water and [foul] purulence.