'Not that, my friend; no. If you know too much you will age too soon.'
She paused; then said softly, after a long look straight into his eyes. 'What avails it to talk? You must act.'
'What is required?' asked Astro in trembling tones, and turning pale.
'You must know a certain word, and you must anoint your skin with a certain unguent.'
'Try. You will find my method simpler than your mechanics.'
The single eye of the smith blazed with the madness of desire.
'You are a simpleton, Astro. Five minutes ago you called magic foolery; now, it seems, you believe in it.'
Astro hung his head, convicted, but unrepentant.
'I wish to fly. I care little if I attain by mechanics or by miracles. What I can endure no longer is waiting.'
'I see, I see. Truly, I pity you. It is clear your brain will crack if you don't get to your flying. Good, then; I will give you the drug and I will teach you the word. But you likewise, Astro, you must do what I ask of you.'
'I will, Monna Cassandra. I will do anything. Speak.' The girl pointed to the wet roof beyond the garden wall.
'Nay. I will do whatever you ask, saving only that.'
'I have promised my master to let none in.'
'No mystery, Monna Cassandra; nothing of moment. Machines, appliances, books, manuscripts. Certain strange plants, beasts, creeping things. Travellers bring them from distant lands. And there is one tree which has been poisoned.'
'Ay. He has it for experiments; that he may know the effect poison has upon plants.'
'Good Astro, tell me all you know of that tree.'
'There is naught to tell. Early in the spring season he bored him a hole in its trunk, to the very core; and with a long thin needle he squirted in some venom.'
'What strange experiments! And of what sort is the tree?'
'What followed? Was the fruit also poisoned?'
'Can you see in the peaches that they are poisoned?'
'No; and that is why he permits no entry, lest some one might eat the fruit and die.'
'Monna Cassandra! Have I not sworn to him?'
'Give me the key; and I will compass it that to-night you shall fly--this very night. See, this is the drug.'
She drew from her bosom a phial which contained a dark liquid; and putting her face close to his, she whispered wheedlingly, 'What is it you fear, simpleton? You say there are no mysteries. Well, then, let us go and make sure. The key, Astro, the key!'