An aerosol generator device for delivering an aerosol of a nicotine salt is provided. The aerosol generator comprises: (i) a mouth end; (ii) a first chamber containing a porous material wetted with liquid nicotine, (iii) a second chamber containing a porous material wetted with a solution of a volatile acid, (iv) a third chamber in fluid communication with the first and second chambers, leading to the mouth end, and (v) an outer housing defining a passageway for air through said device. A nicotine vapor can be produced by drawing air along the passageway and through the porous material wetted with liquid nicotine. An acid vapor can be produced by passing air along the passageway and through the porous material wetted with a solution of a volatile acid. Then, the nicotine vapor and the acid vapor can be admixed in the third chamber to form an aerosol of a nicotine salt, which can be drawn out through the mouth end.