Blood blood clotting in a transparent container. When blood is drawn in a glass container and left undisturbed for about an hour, four different layers can be seen. A dark clot forms at the bottom (the "black bile"). Above the clot is a layer of red blood cells (the "blood"). Above this is a whitish layer of white blood cells (the "phlegm"). The top layer is clear yellow serum (the "yellow bile"). The ABO blood group system was discovered in the year 1900 by Karl Landsteiner. Jan Janský is credited with the first classification of blood into the four types (A,
Super Hits (Blood, Sweat & Tears album) Ultimately, this collection isn't as detailed as Blood, Sweat & Tears Greatest Hits, but it's still a good bargain for the budget-conscious." Super Hits (Blood, Sweat & Tears album) Super Hits is a budget compilation album by the band Blood, Sweat & Tears released by Columbia Records in 1998. This ten song collection draws four songs from each of the band's first two albums "Child Is Father to the Man" and "Blood, Sweat & Tears". Writing for Allmusic, critic Al Campbell wrote, "Super Hits samples ten tracks recorded by Blood, Sweat & Tears for Columbia Records in the late '60s