Do you refer to the first of the four parts of Preludes or just the first one? If it is the first, here goes an analysis---
It presents to us a desolate image gallery that captures a squalid, pointless and boring cityscape and its random happenings which only reinstate stasis. The settling down of the winter evening is made to imitate the movement with which a cat settles down or takes its seat. There is a synesthetic imagery that combines sights, smells, taste and so on. There are smells of steaks and the smoke that comes out of the burnt out butt of a cigar is what the end of the day is compared. There is a connotation of exhaustion and boredom everywhere in this landscape.
The random shower, the grimy scraps, the heap of withered leaves all symbolize a lifeless hollowness of modern day urban existence, so very characteristic of early Eliot.
The lonely cab-horse is the acute symbol of helpless rage, frustration and absolute alienation with which the fragment comes to a close. The lighting of the lamps is like a switch from the darkness so far described and fleshed out in different ways but as the other fragments imply, this lighting is not at all non-problematic.