Samples had been taken from several of the suspect wine casks in Druer's cellar and brought back to the Monastery where the three monks were now sitting at a table deciding what to do next.
"I have been reading some reports from France," Mendel said, as he unpacked his microscope, a valuable piece of scientific equipment he had obtained while a student at University. "A Herr Doktor Pasteur has been addressing a similar problem to this one, but he has been examining fermentations in sugar beet."
"Ah yes," said Brother Joseph carefully cleaning a number of thin glass microscope slides and placing them on the table, "I remember reading something about Herr Doktor Pasteur's results. Didn't he find crystals were involved?"
Mendel scratched his head. "Some of his early work was on the optical properties of certain crystals, tartaric acid I think, and, yes, he did find them in wine vats, but I don't remember anything about them being involved in bad fermentations."
Brother Matthew pushed a chair up to the table and adjusted the light source close to the microscope mirror. Mendel opened the first wine sample and removed a tiny drop by dipping a glass rod into the liquid and then tapping the end of the rod onto the surface of a glass slide. The musty wine sample ran off the rod and formed a tiny puddle on the slide. Trying to keep his hand from shaking, Mendel then lowered a thinner square of glass edge first onto the puddle of wine. This procedure had to be performed with extreme care to avoid trapping air bubbles between the two pieces of glass. His old Professors at the University of Vienna had been very harsh on any student who could not prepare his microscope specimens properly.
With the specimen prepared to approved standards, Mendel placed the sample on the microscope stage, roughly adjusted the light source, the mirror and the level of the microscope lens. Placing one eye to the ocular lens at the top of the microscope, he spent a couple of minutes adjusting the mirror and diaphragm below the stage so as to send just the right amount of light through the specimen. When he was satisfied with the light quality he lowered the lens with the least magnification within a tiny distance of the glass, then he began to focus.
"I'm not sure we will see anything at this magnification," he told his friends, "but we have two other lenses to try when we find something interesting."
For the next hour the three monks took turns at the microscope looking for clues in the wine. They saw grains of sharp edged materials that, under the microscope looked like shattered rocks from an avalanche; they saw soft, fluffy material which reminded Klacel of freshly carded wool, and lots and lots of minuscule dots which floated and drifted aimlessly across the field of view, driven by tiny currents and vortexes in the liquid. Some of the smallest dots vibrated randomly in all directions as if driven by invisible forces. But, while there was a lot to see, nothing seemed to be the obvious cause of the souring process.
"Huhh," snorted Klacel, pushing back the chair from the table and rubbing his eyes, "this is getting us nowhere."
"Perhaps we are looking in the wrong place," suggested Brother Joseph mildly. He and Mendel were both more patient than Brother Matthew, and knew more about the slow pace of certain scientific investigations.
"And where would be the right place?" asked Klacel, an edge on his voice.
"Perhaps here," Mendel answered him, holding up yet another sample.
"And why there?" Brother Matthew retorted.
"Well, we've looked everywhere else," Mendel said with a sly smile at his friend's impatience, "and also, this sample was taken from the bottom of the worst cask. Most of the others were not as sour as this one."
"Let's have a look," said Brother Joseph, taking the sample from Mendel and preparing yet another slide.
Drifting among the debris of the fermentation Brother Joseph finally spotted something. "Look here," he called out to his friends.
"What is it?" Klacel asked after looking down the microscope, which he found set at it's highest magnification.
"What does it look like?" Brother Joseph replied with hardly concealed excitement.
"On the left I can see a cluster of symmetrical oval shapes of different sizes. They are refracting the light and look a bit like bunches of grapes."
"They are budding yeast cells," Mendel told him. "They are found in all fermentations and Herr Pasteur believes they are responsible for the production of the alcohol."
"So they should be here?" Klacel asked, his interest picking up again. "But why didn't we see them before?"
"I'm not sure," Brother Joseph answered, "that might be something to investigate. But I don't think that the yeasts are the cause of the wine going sour. Look over on the right side of the field of view."
Brother Matthew did as he was told. Using his thumbs he moved the slide to the right, watched the yeasts moved out of view to also to the right. He 'tut tutted' to himself, corrected his mistake and readjusted the focus. His eyes were better than both his fellow monks.
"Ahh, yes, now that is something we haven't seen before," he said slowly. "These are different. This looks strange indeed, more like a tangle of tiny rods, some single, but many held together in drifting chains or strings covered in slime. They are much smaller than the yeasts. What are they?"
With barely suppressed excitement Brother Joseph answered him, "If I am not mistaken, they are bacteria."
"What are bacteria?" Klacel asked, not alone in his ignorance.
"No one is exactly sure," Brother Joseph admitted, "but they have been seen before in a variety of situations".
"Professor Unger seemed to think that they were not a true living form," Mendel added, drawing on his lessons from University. "But Herr Pasteur in France identified similar structures in the fermentations of sugar beet that had gone sour. They were certainly alive and growing in his investigations."