The day, notwithstanding it was now October, was intensely hot (although a severe frost for two or three days before gave indications of approaching winter), and the streets being unmacadamized, had that arid look we read of in accounts of the plains of Arabia, the dust being quite deep, and exceeding in quantity anything of the kind I had ever seen in European cities: clouds of it impregnated the air, and rendered respiration and sight difficult.
Source: wiktionary