Alexander Lion, son of an inventor who invented cufflinks in Marseilles(France), designed and registered an incubator for eggs in the same town on October 28,1889. The patent of June 26, 1890 was valid for 15 years. The device was equipped with battery operated heat alarms and automatic gas heating adjustment. In the same document, Lion mentionned and illustrated an adaption he applied in his home successfully to preserve “maternal heat” of an infant born at six months gestation who needed regular, constant and uniform heat to survive. He said other (Tarnier/Auvard)“automatic” types of incubators were rudimentatry glass and wood boxes with unstable heat sources exposing the infants to the risks of burns and hypothermia.

Although technicaly advanced, the Lion device was energy source dependant. The gas pressure on cold nights in Paris was insufficient to heat the incubator, which delayed its general use. Other authors used Denucce/Crede double walled tubs with intermittent hot water heat addition to maintain warmth. In the mild climate of Nice, it was a success for five years, before making a comeback in Paris.

Dr. Pinard modified the metal and glass construction with rounded corners for easy cleaning and steam disinfection to answer Marfan's and Bertin's concerns with wooden style devices. Infants were swaddled with waddings to maintain heat. other supplementary heating was necessary to meet loss by removal during feeding and toiletry.