Marmbilde, i.e. icing, hail is well known to pastoralists in the regions off the Atlantic fassade, because the thermal gradient, * the temperature difference between the hottest and the coldest seasons* is here much more pronounced. :
During the rainy season, short showers of hail may happen and FULƁE call these small hailstones Marmballe . It has been observed, a rainy season with such occurrence will be accompanied by abundant waters and a steady growth of even rare herbs demanding copious and well balanced rainfall, followed by an equally intense cold season (for SAHEL Zone conditions). *By the way, this observation has striking parallel with the highly lyric and descriptive German poem das Jahr im Bauernmund . * Now let's come to our main subject: the Pulaar-Fulfulde states ndiyam na marmbilla (a), na siwa (b), na ayta (c), na wula (d), na wawña (e), na barma (f), na hooñca (g): (pure) water freezes at 0 degree Celsius, (the degree Celsius formerly known as centigrade is abbreviated ℃ in scientific notation, which we'll accordingly henceforth use), then becomes liquid (qualifier b), lukewarm (c), then 'hot' (d), then 'very hot' (e), then boiling (f). The seventh qualifier (g), meaning completely evaporated will not be taken into account for the ensuing discussion.
The six qualifiers refer to temperatures intervals between 0 ℃, the freezing point, and 100 ℃, the boiling point of water. These intervals however have different ranges and do necessarily overlap. Now we set to construct a new scale on the basis of these qualifiers: to that effect we'll re-scale these six ranges into three non-overlapping, consecutive and of equal amplitude ranges. We further subdivide each in 10 units and let the lowest value, which we set 0 unit coincide with 0 ℃ :
therefore the 100 ℃ will fall to 30 units in our new scale. We call the new unit siiwel, (pl. siiwoñ ) which then equals 10/3 ℃ .
The expression werwaylo o marmbalii 4 siiwoñ: the temperature is 4 siiwoñ below freezing point is written as T = -4 siiwoñ = -4*10/3 ℃, which amounts to roughly -13 ℃ . The prefixed minus sign, (-) accounts for temperature values below the freezing point, 0 ℃ , which per convention coincides to 0 siiwel .
**Mi yetti sanne. Yoo PULAAGU wuur, foola. Sehil mon, Pullo PEREEJO**