It seems to be two GS and two Ws intertwined.
"True and Other Stories"
George Parsons Lathrop
July and August are hot and steamy in the valley, and it is necessary to seek one of the cool "MarGS" which form ideal camping-grounds on all the lofty mountain slopes which surround the valley.
"A Holiday in the Happy Valley with Pen and Pencil"
T. R. Swinburne
First there was the dizzying, mind-blackening centrifuge test, to see if you could take enough GS of acceleration, and still be alert enough to fit a simple block puzzle together.
"The Planet Strappers"
Raymond Zinke Gallun