Issaouane Erg confined to basins. Sand in the Issaouane Erg, below the level of the sand dunes, has accumulated to a depth of 20 to 30 meters. It has barchan dunes as well as star dunes of 300 to 430 meters high. The presence of both barchan dunes (which form due to unidirectional winds) and star dunes (which form when winds from various directions deposit sand) "suggests that wind regimes have changed over time". NASA's "Earth Observatory" notes all three types of erg dunes are present in the photos of the Issaouane Erg taken from the International Space Station: stationary mega dunes,
What Are Little Boys Made Of? by Roud number What Are Little Boys Made Of? "What Are Little Boys Made Of?" is a popular nursery rhyme dating from the early 19th century. It has a Roud Folk Song Index number of 821. The author of the rhyme is uncertain, but may be English poet Robert Southey (1774–1843). Here is a representative modern version of the lyrics: <poem> What are little boys made of? What are little boys made of? That's what little boys are made of What are little girls made of? What are little girls made of? That's what little girls are made of</poem> The