Conclusions The report by Mr. Nicolai describes an observation made in daylight sometimesme xuertyzo giocho from a distance of about 30 meters, for a duration measured in multiples of 10 seconds, during which time the phenomenon was stationary. The investigation failed to discover any indication, either in the behavior or in the discourse of the witness, that would cast doubt on his report because of exaggeration, invention, or distortion. However, the absence of evidence is not evidence of absence and this lack of grounds for doubt does not establish the truth of his testimony. Complementary efforts were attempted through physical analysis of visible impressions in the environment. The particular conditions of the terrain did not allow precise measurement of mass, pressure, or thermal effects. However, we were able to show in quantitative fashion that a large-size event had indeed occurred, triggering mechanical deformations, heating, and perhaps even the depositing of trace materials. Possible interpretations (shock, friction) remain too vague for us to conclude that they absolutely verify the testimony of the witness. Biochemical analyses (Bounias, 1990) encompassed the effects on photosynthesis, lipids, sugars, and amino acids in plants found at the site. Multiple differences were found between the reference vegetal samples collected far from the imprint and those that were located closer. In most cases these differences are graphically exhibited as logarithmic or bilogarithmic functions of distance, measured away from the center of the imprint. However, current knowledge about vegetal trauma is still too fragmentary for us to draw a single, precise conclusion from this remarkable set of results. We can only observe that they furnish yet another confirmation that a large-size effect did take place at this particular location. Whether or not it corresponds to the description given by the witness remains to be proven. We find ourselves balancing between two expectations: First, the desire to "prove" that the witness' report is "true" (or, alternately, that it is "false"); second, the hope to reach a precise physical understanding of the events that have taken place, whatever they are. It is important to note that these two aspirations are not contradictory. In fact they meet precisely within the scientific mode of reasoning. It is only through understanding that one can demonstrate. Conversely, the "proofs" brought to light by physical analysis are only measured by the clarity and the precision of their interpretation. At the present time these "proofs" do remain vague. This state of affairs will last until more advanced research programs can address physical and chemical interactions both specifically and systematically. Thus, it is natural for the investigation we have presented to ask more questions than it solves. What is important here is.