The scientific study of blood spatter pattern analysis is fascinating .
Often the crime scene can be recreated from the blood spatters such as :-
Angle of Impact
Where it came from
Number of Blood initiating or Altering Events
Sequence of Events
Handedness of Assailant
How to make Blood!
Artificial Blood Preparation Use 120ml/ 115g of evaporated milk, 2-3 tablespoons of tomato paste, and red food dye. Mix to the viscosity of blood (use water to thin as necessary). Check the viscosity before filling the bottles by dropping the blood from various heights (As in the Lesson Plan) Do also bear in mind that temperature will make a large difference on the blood. This artificial blood mixture should be good for a few days. Store in a refrigerator.