Rising of the lights was an illness or obstructive condition of the larynx, trachea or lungs, possibly croup. It was a common entry on bills of mortality in the 17th century. Lights in this case referred to the lungs.
In culture In his A New Booke of Mistakes (1637), Robert Chamberlain gives a humorous epitaph:
Of one Parkins a boone Companion in Essex who dyed of the rising of the Lights.
References
Further reading Taylor, Mark R. (1926-12-04). "Rising of the Lights". British Medical Journal. 2 (3439): 1081. doi:10.1136/bmj.2.3439.1081-a. ISSN 0007-1447. PMC 2523749.