Thanksgiving History. Thanksgiving is a particularly American holiday. The word evokes images of football, family reunions, roasted turkey with stuffing, pumpkin pie and, of course, the Pilgrims and Wampanoag, the acknowledged founders of the feast.
A forb (sometimes spelled phorb) is a herbaceous flowering plant that is not a graminoid (grasses, sedges and rushes). The term is used in biology and in vegetation ecology, especially in relation to grasslands[1] and understory.
ANSWER: A PVB is a mechanical backflow preventer that consists of an independently acting, spring-loaded check valve and an independently acting, spring-loaded, air inlet valve on the discharge side of the check valve. It includes shutoff valves at each end of the assembly and is eqipped with test cocks.