My main article appeared in Naturwissenschaften in 1995, volume 82, pp. 360-369.



Betz replied  and Ertel did another (misguided) analysis of the data, and

those articles appeared in 1996, Naturwissenschaften vol. 83, starting on

p. 272, and on p. 233; and my response to those attempted defenses was

published in the same journal, also in 1996, volume 83, pp. 275-277.



(Most University libraries ought to have Naturwissenschaften.  It is the

official organ of the Max Planck Society, which is the German equivalent of

the  National Academy of Sciences of the U. S. and the British Royal

Society.)



What kind of response have I had?  None from the pro-dousing community

(other than the Betz and Ertel "rebuttals" mentioned above), but quite a

few e-mails from fellow skeptics.  Among those whose names occur to me now

are Jan Nienhuys, a Dutch mathematician who has published critical articles

on the "Mars effect", and  Norwegian academic named Rolf Manne, who told me

that Betz's experiments had been used in Norway as justification for

government encouragement of the use of dowsing to find people buried by

avalanches.  He was glad to have my analyses and graphs as ammunition to

attempt to counter that superstition.  And, of course, Eric Krieg, and

James Randi.



The endorsement by Nienhuys is the only authoritative "Expert" comment by

someone who understand statistics and experimental design at the level my

article has addressed, but of course there was also an anonymous referee

(also a statistician) who endorsed publication of my original article.



Betz's field trials?  There is a vast literature, going back several

centuries, of anecdotal reports of dowsers' successes.  In 1917, the US

Geological Survey evaluated that literature (up to that date) and concluded

that it was all worthless: "...it should be obvious to everyone that

further tests by the USGS on this so-called 'witching' for water, oil or

other minerals would be a misuse of public funds." (cited from my original

Naturwiss. article).  I do not know the details of Betz's field trials, but

I think there is strong reason to presume that they were uncontrolled

"fishing expeditions", that do not deserve the name "tests", much less

scientific experimentation.  I am willing to grant that there may be some

dowsers who have an intuitive, subconsious understanding of underground

topography that permits them to choose a better spot than just a random

guess; and they may even use a dowsing rod to confirm what their

subconsious tells them.  Even I would, I think, be able to make a guess

about better and poorer places to bore on the basis of obvious superficial

landscape features: don't drill at the top of a hill; look for a gentle

valley with a large potential drainage area behind it, etc. 



I have seen private correspondence from Betz, in which he as much as admits

that the "barn" experiments are not in themselves particularly convincing. 

Quote: "selbst wenn er die Ergebnisse der Scheune nicht besonders werten

moechte (wofuer ich ein gewisses Verstaendnis habe)...", which, in rough

translation, says "Even if he [meaning me] prefers not to put much faith in

the results from the barn (and I have a certain understanding for such a

position)..."  And then Betz says that one should instead put more faith in

what dowsers have been reported to do under field conditions; but it is

exactly that sort of anecdotal reports that, in my opinion, deserves no

more credibility than the claim by my aged aunt, that her knees ache the

day before the weather will change: a typical problem involves failure to

remember all the times that the weather changed without hurting knees, and

all the times that her knees hurt when the weather didn't change-- the kind

of selective memory that has led to all the superstitions in the book.



You ask whether anyone has addressed this point about the field testing,

and I think I must answer in the negative, as far as written comment that

I've seen goes, other than the expression of severe doubts about any sort

of anecdotal evidence without proper experimental controls.



Any more questions that I might be able to answer?



Cheers!

Jim Enright



P. S. Your message, in another place, refers very casually to "earth rays".

 Among those who believe in them, have you found anyone who can tell you

exactly where they fit into the electromagnetic spectrum, and if so, what

sort of physical instrument (other than a dowsing rod) that might be

designed to reliably demonstrate their existence?  It seems a bit naive for

the believers to postulate some new source of energy, with all its

remarkable properties, without being a bit more specific.



Note from Eric, you can subscribe to NatureWissenSchaften by going to:

http://link.springer.de/link/service/journals/00114/subs.htm

This and other dowsing information can be found from:

http://www.voicenet.com/~eric/dowsing.htm