The de la Vega father and son were enjoying lunch at the tavern when a tall stranger entered the doorway.  His calm gaze swept over the room and its occupants.  He was dressed in the uniform of a high-ranking colonial officer, and his confident stride to the bar carried the assurance of one used to command.
     "A room for two nights, if you please, Señorita," he addressed Rosa, the tavern's mainstay of hired help.
     "Certainly, Señor.  This way," the woman replied as she picked up a room key and came around the counter.
     Don Alejandro's head turned as soon as the officer began to speak.  His brow furrowed as he tried to lay hold of some elusive memory.  "Excuse me, Señor," he said, rising from his seat.  The newcomer turned and looked at the older man.  "Aren't you Antonio Seguro?"
     "Yes, I am," replied the stranger with a blank look, "but I'm afraid I don't--"
     "You were a raw lieutenant under my command in Panama.  I'd know your deep voice anywhere."
     Recognition dawned in the eyes of Seguro.  "Of course!  Colonel de la Vega!  An honor, sir, to see you again."
     "You're a colonel now yourself, I see.  What brings you to Los Angeles?"
     "Church business which has been entrusted to me.   I will only be in town about two days.  I've four men with me who have been billeted with the garrison."
     "And you must come and stay with us at our hacienda.  Oh, this is my son, Diego."  The two men shook hands.
     "Mucho gusto, Señor.  I thank you for the kind offer, Colonel, but unfortunately, being in town will be more convenient for my purpose."
     "Then I insist you join us for dinner this evening.  I'll send the carriage for you at seven o'clock."
     "Gracias, Colonel.  Until seven, then."

     "Diego, there was not a more promising junior officer in my command than Antonio Seguro here.  Even in his first battle, he displayed the poise of a hardened veteran."
     Seguro laughed.  "Your father exaggerates, Don Diego.  If it hadn't been for his fearless leadership, half of us would have turned tail and run."  He paused.  "His Majesty lost a fine officer when you sold your commission, sir."
     Alejandro sighed wistfully.  "Often I've missed the army.  But life isn't long enough to do everything, and I had other responsibilities.  My wife wanted to settle down, and my father's health was poor.  He needed me here to manage the rancho for him while he lived.  And of course, that tiny thing sitting at the end of the table needed a full-time papa."
     Diego smiled.  His father was proud that his only son had outgrown him and rarely lost an opportunity to mention it.  He entered the conversation, "You, instead, became a career officer.  What now for you that Mexico's declared independence?"
     Seguro shook his head.  "Being a colonial myself, I'm both fish and fowl, so to speak.  It's a delicate line to walk sometimes, but for the most part I'm left alone.  Fortunately, my current business has nothing to do with politics."
     "Something with the church, you said."
     "Yes, it's not a secret though for reasons which will be obvious, neither have details of this shipment been made public.  The bishops in Mexico City would like to see the California missions strengthened, not only to spread the word of God, but to serve as focal points for community life as the pueblos up the coast grow larger.  To that purpose, they have sent a shipment of gold ingots to be distributed to the churches to finance this vision.  The risk of robbery was thought to be too great to send the gold overland, so it's arriving by ship in San Pedro quite late this evening.  It is my task to accompany the gold from here and see to its proper distribution among the missions."
     "An important task, indeed.  The bishops made a good choice in you."
     "Gracias, Colonel.  Now if you gentlemen will excuse me, I must rejoin my men.  We will have to leave shortly.  I thank you for the delicious dinner and most wonderful companionship.  Buenas noches."

     In Diego's hidden laboratory, the caballero continued Felipe's education in the sciences.  "An element is a chemical substance which is in its simplest form.  In other words, it can't be broken down into any simpler substances.  The ancient Greeks believed there were only four elements:  earth, fire, air, and water.  Now we know that none of the four are true elements, but compounds of elements.  Science has since isolated and identified quite a few, such as oxygen, hydrogen, carbon, and certain metals such as gold, silver, copper, lead, and so forth.  The difficulty in naming a substance an element is determining whether or not it's a simplest form.
     "Men in the middle ages thought everything was made up of the same basic chemicals, and if they could just find a way to change the proportions, they could change baser materials into finer substances such as turning lead into gold.  Of course, now we know such a thing is impossible.  Elements don't change.  But for years, a false science called alchemy developed from men trying to do just that.  Enough for tonight.  Let's get to bed."

     The autumn evening was quite advanced when the colonel and his men arrived in San Pedro to oversee the off-loading of the strongbox containing the gold.  The heavy chest was lifted onto a garrison wagon, and Seguro signed receipts accepting the transfer from the official who had accompanied the gold from Mexico City.  Their business concluded, the five soldiers turned toward the Camino Real with their precious cargo.  The road north was dark since the moon was in its first quarter, and the fifteen miles back to Los Angeles began to slip by uneventfully.  The long quiet ride and lateness of the hour had combined to relax the alertness of the guards when nine masked riders charged toward the wagon from behind a grove of trees.
     "Get the wagon!" shouted the bandit leader.  In response, one of his compadres jumped on the wagon seat, struck the driver across the face, and pushed him off.  Seizing the reins, the bandit whipped up the horses faster.  Meanwhile, the colonel and his three remaining men were fighting hand to hand with the highwaymen but were overwhelmed by greater numbers.
     What a peculiar encounter, thought the colonel.  The thieves did not try to shoot his soldiers, though they had all been disarmed.  They seem more interested in delaying our pursuit.
     As suddenly as they had attacked, the highwaymen disappeared.  The leader called, "Vamanos!" and the eight men rode off, each in a different direction.
     Seguro shouted a command, "Never mind the bandits; after the gold!"  His men dug in their heels, and they all followed their colonel at a full gallop.  Three miles to the north a large object was blocking the highway.  "Whoa!  That looks like the box.  Open it, private."  Indeed, the strongbox was lying on the road, apparently abandoned by the driver of the wagon.  As the soldier forced open the lid, the golden ingots were seen gleaming in the dark night.
     "Gracias a Dios," breathed the officer gratefully, making the sign of the cross.

     "Hola, Colonel Seguro!  Did your assignment go well last night?" called Don Alejandro, riding into the plaza accompanied by his son.
     "Buenos dias, sir, Don Diego," replied the officer.  "It was quite an exciting night.  A robbery attempt was made on the gold, but it is now secured in the alcalde's jail until we leave tomorrow morning."
     "A robbery attempt?  Was anyone hurt?" asked Diego.
     "No, thankfully.  But the whole incident was highly unusual."  He related the story to the caballeros.  "Two things puzzle me.  First, that they didn't try to hurt us, and that they ran off after delaying our pursuit of the wagon, though they had us outnumbered.  Then, why did they abandon the gold for which they had risked so much?  In the darkness the wagon driver could have easily eluded us by driving off the road."
     "Perhaps the gold was heavier than the thieves anticipated.  The driver panicked and pushed it off in order to get away," suggested Alejandro.
     "I doubt if one man could have pushed it," Seguro reasoned.  "But 'All's well that ends well,' as Shakespeare said.  I hope I'll see you again before we leave."

     Diego was in a pensive mood all afternoon.  He sat in the library with a book opened in front of him, but his eyes were not focused on the pages.  When Felipe came in the room, his mentor looked up.
     "The Colonel's correct, Felipe.  Something's peculiar about that robbery attempt.  I have the strangest hunch--"  He shook his head, frowning.  "I think Zorro will pay a visit to the jail tonight."

     Sergeant Mendoza was eating his supper at the alcalde's desk.  It had been his dubious honor to be selected to guard the gold shipment during the night.  He was reflecting on how many times he had pulled guard duty over inanimate objects when the skylight opened, and a masked man dropped down from the rafters.
     Mendoza choked on his stew and sputtered, "Zorro!  What are you doing here?"
     "Good evening, Sergeant.  Forgive me for interrupting your meal.  This is not a courtesy call; I have business with the gold in your jail."
     "You came to steal the gold?  Zorro?  I can't believe it!"
     "Don't worry, my friend.  I only want to borrow one ingot."
     "I--I can't let you.  That gold belongs to the churches," replied Mendoza sternly.
     Zorro drew his sabre smoothly from the scabbard and tapped the soldier's chest.  "I really must insist, Amigo.  Trust me.  Now the keys, please."
     "All right," the sergeant replied, fumbling with the keys, "but I'll have to tell the alcalde and the colonel."  He unlocked the cell door, and went in with the dark hero.  Together they raised the heavy lid.  Zorro lifted out an ingot and examined it carefully. He did a cursory inspection of the rest of the box, thanked the lancer, and left the same way he had entered, taking the gold bar with him.
     Back in the cave, Zorro explained to Felipe the experiment he was about to perform.  "One other thing about a element; each has its own mass.  I remembered a story about Archimedes using his knowledge of the elements to discover a fraud.  It seems a king had commissioned a crown to be made of pure gold, but when the goldsmith presented it to him, the king suspected that the crown might not be pure.  He called Archimedes to see if the scientist might be able to tell, without destroying the crown, whether or not the king had been cheated.  Archimedes found the answer in volume.  He compared the amount of water displaced by the crown to an equal weight of pure gold.  Gold is a very heavy element for its size, remember.  The crown displaced more water.  The goldsmith had mixed silver with the gold and kept the difference.
     "Now here is a pile of solid gold pieces of eight that belong to my father.  I've weighed the ingot and measured out an equal weight of coins.  Now let's see--"  Zorro lowered the ingot into a graduated beaker filled with water.  He wrote down the measurement, then replaced the golden bar with the coins.  "Look there, Felipe!  The money is replacing less water than the ingot."  He picked up the ingot and scratched a deep gouge in it with a knife.  He showed it to his companion with a smile.  "This is a gold overlay on another metal.  It looks like lead.  The colonel was robbed on the highway last night, and it was done so cleverly that no one would have ever guessed."  Felipe pointed with grin to the masked man.  "Well, yes, except me," he acknowledged modestly.  "The trail is a day old, and time is short," he added, reaching for his hat.

     The alcalde was furious with his sergeant, who was rigidly standing at attention.  The colonel was also displeased to find that an ingot had been stolen.
     "Sergeant Mendoza!  Why didn't call for help when Zorro came into my office?  How could you let him take the gold and leave without stopping him?"
     "I tried to, Alcalde, but Zorro had his sword pointed right at my heart.  He said he just wanted to borrow the gold for a little while.  Doesn't that mean he will bring it back?"
     "You imbecile!  Don't you know yet you can't trust a thing he says?  You'll pay for the gold, if you have to spend forty more years in the army to do it!" bellowed DeSoto.
     "Who is this Zorro?" asked the colonel.  "Can't we track him?"
     Mendoza would have loved to give his views on the outlaw, but the alcalde answered hotly, "He's the worst bandit in the territory and has been a thorn in my side ever since I came here.  As for tracking him, impossible.  We've tried dozens of times, and he has always eluded us."
     "Then there's nothing more to do except load the rest of the gold in a wagon and be on our way.  A sorry beginning to my assignment, with the loss of some of that which was entrusted to me," the unhappy officer commented.
     "Sergeant Mendoza, prepare a wagon for Colonel Seguro, and get the strongbox loaded."
     An hour later the garrison gates opened, and a wagon drove through surrounded by an escort of mounted guards.  The colonel thanked the alcalde for the garrison's hospitality and gave the order to move out.
     "One moment, Colonel!" called a loud voice from the roof of DeSoto's office.  Every head turned to find the speaker.
     "Zorro!  Lancers, shoot him!" shouted the alcalde.  Several alert soldiers swung their muskets around and fired at the masked man, who dropped down to avoid being hit.
     "Colonel!  The cargo in the wagon is not what it appears to be!" the dark hero announced.
     "Señor Fox, you have my gold.  I want it returned.  I appeal to you in the name of the church."
     "I will gladly return this ingot to you.  Examine it carefully."  He threw it high in the air, and it landed with a thud at the feet of Seguro's horse.  The colonel dismounted and picked it up.
     "What is this?  Explain!" he demanded, after observing the scratch.
     "Colonel, you were successfully robbed the other night on the highway, and this box of gold-plated lead was substituted for the real gold.  Check the other ingots in the wagon."
     Seguro looked hard at the masked man, then ordered, "Stand down your weapons."  Every soldier obeyed.  The officer climbed into the wagon, lifted the lid, and gouged several ingots with his knife.  "You are right, Señor!" he called out.  "Every one of these is a fake.  Men, we must find the stolen gold.  Let's ride!"
     "That will not be necessary, Colonel.  The gold is resting safely in the sanctuary of the church," assured Zorro, pointing across the plaza.  "You will also find the thieves there, doing a proper penance."
     The officer dispatched one of his men to confirm the dark hero's words.  The private returned running.
     "Everything is just as the masked bandit said, Colonel.  The gold is there, and the thieves as well."
     Seguro's face reflected his relief.  "I and the churches are greatly indebted to you, Señor Zorro.  Thank you for coming to our aid."
     The masked man saluted from the rooftop.  "May the rest of your journey be successful.  Vaya con Dios!"

     Late in the afternoon, the de la Vegas saw Colonel Seguro leaving the alcalde's office.
     "Gentlemen!  I'm able to say farewell to you after all.  Our departure has been delayed one day because of the robbery.  We've had to verify the gold and issue criminal proceedings against the bandits.  Apparently they discovered details of the gold shipment months ago and planned the substitution.  They knew if they didn't kill any of my men that we'd be unlikely to pursue them once we'd thought we'd recovered the box of gold."
     "Yes, and by the time the fraud was discovered, it would have been too late to try to find the thieves," added Diego.  "It was almost the perfect crime--the robbery that wasn't."
     "Almost, thanks to your local outlaw hero.  What a fascinating character!" laughed the officer.  "He has a sense of humor too.  We found the true strongbox in front of the church's altar, and the bandits tied up in a kneeling position before it."
     Alejandro joined his laughter.  "So you'll be leaving us in the morning?"
     "Yes.  I've already allotted Padre Benitez his share, and our next stop will be the Mission San Gabriel de Archangel.  After that, Santa Barbara and so on up the coast.  I've received additional troops from the alcalde so any further robbery attempts are less likely to be successful."  He looked around at the open countryside and the clear blue sky.  "California is a lovely place; I can see why you've settled here.  Perhaps my assignment will help others to enjoy its benefits also.  Colonel de la Vega, Don Diego, it has been my sincere pleasure to renew acquaintance.  Adios."  He shook hands with father and son and returned to the tavern.
     "Diego, there goes one of the finest men I've ever known.  His character was unimpeachable as a young man, and thirty years later he's just as decent and strong."
     "A man of good character is like a solid gold ingot--pure and uncorrupted all the way through.  Such men are a privilege to know."