Sentence:  It is true, the atmospheric regions, at first subnuvolar, soon became enubilated; and old Sol did not radiate his sudorific caloric so potently as on the hesternal day, but the roads had, in some places, become lutulent and somewhat clarty; presenting a great difficiliation to my <WSD>incessive</WSD> velocity, on account of the viscosity of the surface. 
Meaning of the word marked with <WSD> tags:  Intense and active.