This turned out to be a good financial decision for NFG in the 1940s and 50s , when increased demand for natural gas led to long pipelines in the eastern states being connected to new pipelines and fields in the southwestern states . This turned out to be a great financial asset to NFG in the 1940s and 50s , when skyrocketing demand for natural gas led to extensive pipelines in the eastern states being connected to new pipelines and fields in the southwestern states .