"What are we looking at?" Watson asked, peering through the microscope.
"The adrenal glands of a capuchin monkey of South America."
"Oh? Why are we looking at it?"
"For no reason that matters now," Holmes said with a sigh. "My experiment did not show the results I was hoping for."
"You seem upset about that."
"It is a bit inevitable that I should be. After all, I thought I might have stumbled across something unexpected."
"But doesn't this mean our client will escape the hangman's noose?"
"Yes."
"Well then I, for one, am glad."
"Yes, I suppose I should be as well. But is it wrong of me to want to have a hypothesis proven true? May I not wish to make scientific progress even if it is at the expense of my client?"
"Of course not. Nor is it wrong of me to be glad he will live."
"Of course," Holmes agreed. "You keep me grounded, my friend, with your solid moral sense. I thank you."
"Oh," Watson said. "Um, of course."
Holmes stepped away and stretched. "I will have to find a new experiment to perform," he murmured. "After all, there are new discoveries to be made, and I intend to be the one to find some of them."
Watson smiled proudly. "Yes, Holmes, I'm sure you will be."
For the prompt from Michael JG Meathook: Monkey extract.