VERY FINE APPEARING BOTTOM MARGIN ARROW BLOCK OF FOUR OF THE RARE GROUNDED PLANE VARIETY.
The true Grounded Plane stamps, in which the wheels of the plane break through the top of “Cents”, come from various portions of three different sheets. The discovery sheet was owned and broken up by John Klemann Jr. of Nassau Stamp Company. A second sheet was discovered in 1946 and sold in the Thomas A. Matthews sale (H. R. Harmer, Nov. 4, 1964), where it was purchased by Georges A. Medawar, publisher of Sanabria Airmail Catalogue. In Linn's Stamp News (April 21, 1986), Joe Kirker published his research identifying a third sheet as the source of the Grounded Plane variety.
The strong downward shift of the vignette ties this block to the Totally Grounded stamps offered in lots 19 and 20 in this sale. It is not from the Matthews-Medawar (Sanabria) sheet -- the bottom arrow block was divided into singles -- so it must come from either the Klemann sheet or the Third Sheet.