:twocents: He's describing the TECHNIQUE of concentrating the microscopic "solids" that may exist in ANY fluid. In his example, he is referring to POOL H2O. The sample of pool water TAKEN from the suspect pool ON or ABOUT the estimated time of death COULD show the diatoms which MIGHT have been present in the victim's remains.
Th SAME technique (BUT without the addition of the pool H2O) c\would be applied to the victim's body fluids, if present, and to macerated remains. (that in this case would be bones).
Both described techniques require that the examiner evaluate the sediment (solids on th bottom of the test tube) under a microscope.
Final point of the evaluation would be the comparison of the diatoms IF present in the victim's exemplar to those of the H2O sample. IF there's a match of diatoms, THEN the point of presumed drowning has been identified and IF there are diatoms present within the victim, then drowning MUST be considered as a COD and then further evaluation/discussion would be valid regarding MOD.
:twocents: While not meant to be a lecture, it IS meant to be an example of ONE point to illuminate folks on the steps involved by the clinicians in the field of pathology, be it anatomical, clinical or forensic.