Originally Posted by
djwpe
Gary-
i grant you that the biofilm idea is speculative. But it is informed speculation based on my professional experience dealing with commercial and industrial water systems, and seeing the biofilms that exist in these environments.
My problem with this is that the speculation may not in fact be well informed, but rather just the result of simplistic faulty reasoning. This happens as much among professionals as anyone else.
In these particular cases, the the reliability or shakiness of the reasoning depends on how similar in RELEVANT respects things like biofuels and industrial water systems and their biofilms are to synthetic valve oils and their environments. Such analogical reasoning is notoriously undependable unless the relevant similarities are very strong. I don't know whether they are in these "gunk and slime" cases, and so far I haven't even seen any claims that they are -- only that everything involved is "synthetic". It's like "Tropical hardwoods and northern hemisphere hardwoods are both hardwoods and so can be expected to exhibit the same sort of toxicity and resulting skin irritation to woodworkers." Uh, no.
An extreme example of such reasoning is one I still recall from one of my very first logic courses: "Russians are red and fire engines are red, so therefore Russians are fire engines." (It had a bit more sense and humor in the era of the Soviet Union, but is still a good example ). What we have here (so far as I can see) is the parallel "X is a synthetic oil/fuel product and synthetic valve oil is a synthetic oil product, and therefore the slime in instruments using synthetic valve oil has the same causes as the slime observed in cases such as biodiesel or industrial water systems." However, on the face of it there appear to be HUGE differences between the environments involving biofuels and industrial water systems on the one hand and the innards of my euphonium on the other. In addition, we don't NEED such speculative analogies. We can actually, in the laboratory, determine what the cause of the slime is in each case. And, scientifically speaking, it should be quite easy to do so in the case of musical instruments (as illustrated by the suggestion that it's a good project for high school science students!).
I see things going on in my home water system that don't show any evidence of appearing in my instruments. So that would seem to count as a counter-analogy to the commercial water system analogy and the biofuel analogy.
So based on your professional experience, can you make that analogy more reliable and convincing by tightening it up in terms of the specific chemistries involved, the specific bacteria involved, and the particular reactions involved? Maybe these really ARE very similar (but maybe they're NOT -- I just can't tell from anything that's been said so far). That would take a significant step toward making those analogies less speculative and more convincing. If we know the same bacteria occur in both environments (do we?), and if we know that the same (or relevantly similar) chemical molecules occur in both environments (do we?), and if we know how the bacteria work to produce the green slime in the one case, then (voila!) it seems reasonable to conclude that they do it in the other case as well. Not completely convincing, maybe. But at least an excellent empirically supported hypothesis.
Last edited by ghmerrill; 02-10-2019 at 01:10 PM.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)