蓋 means 'lid'

As all four kanji represent containers or lids, the essays abound in canning and bottling goods, whether jam or tuna, beer or shochu. Food preparation takes center stage, from grinding spices and kneading dough to cooking mushrooms in a teapot. Things heat up with hibachis, kettles, steam boilers, and the "cauldron of hell"! More unexpectedly, Buddhism keeps popping up, what with ritual vessels and mendicant priests who carry begging bowls. Body parts serve as metaphorical lids and pots. And with more figurative leaps we touch on opening the lid of one's mind and bottling youth.