As the investigation into the Boston Marathon bombing entered its third day, forensic specialists with the FBI, ATF, and local law enforcement continued to review countless photos and videos. And while officials asked citizens to help find the suspect and Internet gurus helped make sense of the "bag or backpack" holding the explosives, important details have emerged from the "ends of the Earth" effort to understand the bombs themselves. At a press briefing early Tuesday evening, FBI special agent in charge of the investigation Richard DesLauriers said analysts at headquarters in Quantico were examining black nylon that could be from a backback which appeared to contain BB guns and nails, "possibly" in a pressure cooker device. Later Tuesday evening, the FBI released two photos — a scrap of black nylon and a hunk of metal — and by Wednesday morning more images had emerged: pictures of the debris from the explosions taken by investigators that combined to become, well, bomb parts. The FBI will try to reconstruct the bomb for answers, and the next briefing is scheduled for early Wednesday afternoon, but as the investigation moves from its "infant" stages to immediate forensics analysis that could lead to answers, the bomb parts and the crime scene itself provide an early public assessment for this crowdsourced investigation.