Bugliosi's 53 pieces of evidence. And WCR link.

[John Iacoletti]

I'll see your Cortlandt Cunningham and raise you a Vincent Guinn.

"Today, Dr. Vincent P. Guinn called the FBI Laboratory and spoke to SA John F. Gallagher. He advised that since the assassination a large part of their efforts have been directed to the determination of powder residues taken from the hands and cheeks of individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald. He advised that there appears that triple firing of this rifle will leave unambiguous positive tests every time on the paraffin casts. It further appears that washing the casts with diphenylbenzidine does remove one of the characteristic elements (barium) but such washings do not remove all of the other characteristic element in powder residues (antimony). Further be advised that the tests to date indicate that powder residues are deposited on both cheeks of the shooter after the rifle is fired either one time or three times. It appears, he added, that these results can be obtained even if the paraffin casts are made 2 1/2 hours after shooting the rifle providing that the skin of the shooter has not been washed in the meantime."

[Tim Nickerson]

I'll see your Cortlandt Cunningham and raise you a Vincent Guinn.

"Today, Dr. Vincent P. Guinn called the FBI Laboratory and spoke to SA John F. Gallagher. He advised that since the assassination a large part of their efforts have been directed to the determination of powder residues taken from the hands and cheeks of individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald. He advised that there appears that triple firing of this rifle will leave unambiguous positive tests every time on the paraffin casts. It further appears that washing the casts with diphenylbenzidine does remove one of the characteristic elements (barium) but such washings do not remove all of the other characteristic element in powder residues (antimony). Further be advised that the tests to date indicate that powder residues are deposited on both cheeks of the shooter after the rifle is fired either one time or three times. It appears, he added, that these results can be obtained even if the paraffin casts are made 2 1/2 hours after shooting the rifle providing that the skin of the shooter has not been washed in the meantime."

 
"We fired the rifle[CE-139]. Mr. Killion fired it [CE-139] three times rapidly, using similar ammunition to that used in the assassination. We reran the tests both on the cheek and both hands. This time we got a negative reaction on all casts." 

                                                                               VS

"powder residues taken from the hands and cheeks of individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald."


How could you possibly conclude that the latter even matches the former, let alone that it raises it?

 

[Colin Crow]

Nitrate test vs NAA.....apples and oranges.

The paraffin/nitrate test was known to be worthless since the 1930's. It was usually used to try and obtain a confession from unknowing suspects.

The NAA analysis of Oswald's cheek cast gave "interesting" results.....

[Tim Nickerson]

Nitrate test vs NAA.....apples and oranges.

True. But why even mention that here?

The NAA analysis of Oswald's cheek cast gave "interesting" results.....

Hmmm....I don't recall the results being all that interesting.

[Colin Crow]

True. But why even mention that here?

Thought it easier for those that didn?t know rather than having to plough through tortuous WC testimony.

[Gary Craig]

"Is it possible to fire a bolt-action rifle and not get any traces of nitrate on your cheek?"

http://www.patspeer.com/chapter4e%3Acastsofcontention
Pat Speer
Chapter 4d: Casts of Contention
What we're not supposed to know

~snip~

The next morning, on 11-23-63, Dr. M.S  Mason and Louie Anderson analyze the paraffin casts of Oswald?s cheek (Exhibit #1), left hand (Exhibit #2), and right hand (Exhibit #3) created by Detective Barnes. The request form for this test, found in the Dallas Archives, records the time of the request as 11:05 A.M. The results read as follows: ?No nitrates are found on Exhibit #1. Nitrate patterns consistent with the suspect having discharged a firearm were present on Exhibits #2 and 3. The pattern on Exhibit #3 is typical of the patterns produced in firing
a revolver.? As Oswald is reported to have handled his revolver in the movie theater these results do little to establish that he?d fired a rifle at the President. More clearly, the positive result on Oswald's hands suggests that the elapsed time since the shooting was not the cause of the negative result on Oswald's cheek, and that one might reasonably suspect he did not fire the shots that killed the President. But does the Dallas Police Department admit to itself or the media that there may be suspects still at large?

~snip~

On 2-27, Dr. Vincent Guinn of General Atomic, whose early offers of help had been rebuffed by the FBI, but who'd later been contacted by the AEC, returns to center stage. A Jevons to Conrad memo relates: "Today, Dr. Vincent P. Guinn called the FBI Laboratory and spoke to SA John F. Gallagher. He advised that since the assassination a large part of their efforts have been directed to the determination of powder residues taken from the hands and cheeks of
individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald. He advised that there appears that triple firing of this rifle will leave unambiguous positive tests every time on the paraffin casts. It further appears that washing the casts with diphenylbenzidine does remove one of the characteristic elements (barium) but such washings do not remove all of the other characteristic element in powder residues (antimony).
Further be advised that the tests to date indicate that powder residues are deposited on both cheeks of the shooter after the rifle is fired either one time or three times. It appears, he added, that these results can be obtained even if the paraffin casts are made 2 1/2 hours after shooting the rifle providing that the skin of the shooter has not been washed in the meantime.  He inquired if any information could be furnished him relating to the actual casts from
Oswald. He stated he read about those casts in the newspapers but has no way to confirm the stories. SA Gallagher advised he was not at liberty to discuss this matter. Dr. Guinn asked who in Dallas might be knowledgeable on this subject. He was advised that he could not be given any information relative to these casts at this time."

~snip~

[Bill Brown]

I'll see your Cortlandt Cunningham and raise you a Vincent Guinn.

"Today, Dr. Vincent P. Guinn called the FBI Laboratory and spoke to SA John F. Gallagher. He advised that since the assassination a large part of their efforts have been directed to the determination of powder residues taken from the hands and cheeks of individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald. He advised that there appears that triple firing of this rifle will leave unambiguous positive tests every time on the paraffin casts. It further appears that washing the casts with diphenylbenzidine does remove one of the characteristic elements (barium) but such washings do not remove all of the other characteristic element in powder residues (antimony). Further be advised that the tests to date indicate that powder residues are deposited on both cheeks of the shooter after the rifle is fired either one time or three times. It appears, he added, that these results can be obtained even if the paraffin casts are made 2 1/2 hours after shooting the rifle providing that the skin of the shooter has not been washed in the meantime."

"We fired the rifle[CE-139]. Mr. Killion fired it [CE-139] three times rapidly, using similar ammunition to that used in the assassination. We reran the tests both on the cheek and both hands. This time we got a negative reaction on all casts." 

                                                                               VS

"powder residues taken from the hands and cheeks of individuals who have shot a rifle similar to the one reportedly owned by Lee Harvey Oswald."


How could you possibly conclude that the latter even matches the former, let alone that it raises it?

Welcome to the new forum, Tim.

[Larry Baldwin]

Welcome to the new forum, Tim.

So, with conflicting testimony, who is to be believed?  We do know that the FBI laboratory ran multiple tests and all yielded a positive reaction on the casts.  However, Cunningham never stated how many tests they ran before casts yielded a negative reaction.  He only provides the results of a "Mr Killian".  Of course the question is never asked "how many times", and thus we are led to believe that there was just one test.  If there was only one test and the results were negative, it was clearly a fluke (considering the multiple positive tests).  If there were multiple tests with one negative result, how many?  We then could play the odds to determine whether or not it was likely that LHOs tests would have a positive reaction.