Keywords: Caterpillar D4 Antarctica 1957.JPG Photo of a Caterpillar D4 tractor pulling newly delivered supplies to the base station at the Antarctic http //www ebay com/itm/1957-Caterpillar-D4-Tractor-Sleds-Antarctic-Navy-Photo-/160676796481 pt Art_Photo_Images hash item2569155841 ht_2843wt_1397 eBay item http //173 12 230 44/yaz317 jpg photo front http //173 12 230 44/yaz318 jpg photo back 1957-06 United States Navy Note that while Caterpillar sent the photo with information to the press the company credited the U S Navy for the photo PD-USGov-Military-Navy Caterpillar D4 |