A comparative look at Italian rapier texts will reveal how Francesco Marcelli’s prima differs from the guard of first advocated by most other masters. First is an iconic guard/parry, and dramatic in most depictions. We see it, amongst many works, in:
- Camillo Agrippa, ca. 1553 (born Milan, active in Rome)
- Fabris, 1606 (Padua, Denmark)
- Giganti, 1606 (born Fossombrone, central Italy, active in Venice)
- Capo Ferro, 1610 (born Cagli, central Italy; active in Seina, Tuscanny)
- Alfieri 1640, (Padua, under Venetian power)
- Pallavicini (1670, Sicily)
I asked Christopher Holzman, who translated Marcelli into English, why Marcelli’s prima is effected so differently, and he suggested that the master’s choice of “prima” as the term for his preferred guard likely reflects its importance. That’s certainly plausible. It stands out against the choice of other Neapolitan masters, especially Pallavicini. This master, who was not one to miss a chance to take shot at his rivals, complains about modern masters breaking tradition. Though he appears to have respected the elder Marcelli, he didn’t think much of some of his later students. He seems especially to have had it in for Francisco Antonio Mattei (author of Della Scherma Napoletana, 1669). Mattei, like Giuseppe Villardita (1670), was a student of Mattei’s older brother, Giovanni, who was taught by the elder Marcelli, Giovanni Battista.  Set side by side, the works by both Mattei and Villardita pale in comparison to those by Pallavicini and Marcelli—they’re not particularly eloquent, well-organized, or as comprehensive. It’s possible that Francesco Marcelli’s guard of first he learned from his father, but at the time of this post I’ve not yet discovered whether that is so or not.
Setting aside the questions of origin and development, for the instructor teaching Neapolitan rapier there are some considerations to manage prior to the lesson. Prima, as Marcelli presents it, reads and functions much differently than the prima/prime of more recent schools. Anyone trained in foil in the late 20th century, for example, likely learned either the French or Italian parries for first. The French school’s parry, in the United States, is probably better known, but the Italian is as venerable. Neither of these assists one in understanding, using, or teaching Marcelli’s version.  If the instructor is familiar with smallsword treatises, then they may know the two key versions found within that corpus, the earlier false-edge parry of prime and the later, true-edge parry that gave birth to the guard of the same name of the modern French school. 
Compared to any of these iterations the low, almost-flat third or oddball second of Marcelli’s prima seems strange. Preconceptions about what first is must thus be abandoned and The Rules of Fencing’s advice taken instead. The hand and blade are held lower than third, and too low for more recent versions of second. Marcelli provides us an illustration, but as always one must consider any image against what the author says. Of prima Marcelli writes:
La Prima Guardia, la dimostra il Cavalier I. nella presente figura; & ella si fà, quando (situato sù la pianta accennata,) si porta avanti il braccio della Spada, tenendo la mano di mezza quarta; e la punta di essa, fermata in angolo retto, starà equalmente alta del pugno, che la sostiene; e tenendola così bassa, si porta sempre per sotto la lama del nemico.
In the present illustration, Cavaliere 1 shows the First Guard; it is made when (situated in the indicated stance) the sword arm is brought forward, keeping the hand in half-fourth, and the point is in the right angle, equally as high as the hand that holds it. Keeping it so low, it is always carried below the opponent’s blade. 
Charles Blair remarked that “Marcelli [Giovanni Battista] was known for a lightning-fast lunge: before one realized what was happening, one was hit; therefore, one could not craft a defence.”  Hyperbole aside, though seemingly open this guard is effective and difficult to confront, and it’s possible to launch a quick attack from it. This should not, to any student of modern epee, be all that surprising. This is essentially the guard often used in that weapon.
While knowledge of modern epee might help, rapier is different enough in weight, length, and context to change a few things. This is not to say that one can’t use modern epee technique in rapier—the SCA’s “Black Tigers” do a bang-up job of using modern fencing in this way, complete with an assumed ROW if the lack of concern about being hit is any guide. However, if one is working from the textual evidence in rapier works, it makes sense to note the parallels with today’s epee and then set them aside.
Warm-Up Drills from Prima
I often start rapier lessons with stop-thrust/arrest drills. It’s a nice way to loosen up the arm, work some point-control, and practice closing the line simultaneously. Typically, I have the student in prima (or whichever guard we’re working on) and make the arrest to my arm as I make purposefully poor attacks.  I start these from various guards and attack in different lines. We start slow, but the purpose is to increase the pace so that we end up in situations the student might face in a bout at speed. They will encounter fencers who attack poorly as well as those who attack properly, and must be prepared for both.
A second warm-up drill is simple parry-riposte. In this case, however, I leave out the purposeful mistakes and increase the difficulty as we proceed. For example, student is in prima; I’m in terza or third. First, I may make a direct thrust to the inside line; the student, from prima, parries in quarta or fourth and ripostes with opposition. Depending on the student, this takes two forms; with my advanced students, for example, they work this as both a one-tempo action and as a two-tempi action, meaning that in the first instance the parry and riposte are simultaneous, in the second the parry and riposte are distinct, sequential actions.
Lessons with Prima
Marcelli, like many masters of his time, breaks some maneuvers into those made with a firm-foot and those made advancing. I use this distinction as well to organize the lesson. For example, firm-footed, I may have the student work on gaining the blade from a specific starting position. Marcelli, in Ch. VII of Part One, Book II, cautions us wisely on the dangers of seeking to gain the blade—if done poorly the opponent will see it and disengage to strike in tempo. Working this action from different distances helps a student learn to make taking the blade effectively and with less danger to themselves as they do so—were we only to practice this in measure the student would have less success outside that specific distance (which is, after all, somewhat relative to the opponent).
From prima, which is below the opponent’s blade, engagements or gaining the blade take, initially at least, specific forms. It is a fantastic guard to adopt against an opponent interested in gaining the blade too—the arm is withdrawn so the point is less easy to defy and secure. Offensively, however, it is fantastic. I usually have the student keep the blade still part of the time, then shift it from guard, constantly shifting aim both to increase the difficulty it taking their blade and to keep the opponent (in this case me) guessing. It is not difficult to effect engagements, beats, or feints from prima. As Marcelli commented, one is well situated:
La Prima Guardia è più secura dell’altre due; e si rende padrona della propria spada più di quello, che sà la Seconda, e la Terza. Poiche in essa, tenendosi il braccio dritto dolce, e curuato, si mantinene anco ritirata la punta, che non stia molto soggetta alla discrettione del nemico. E da questa situatione ancora nascono molto veloci le stoccate, per lo spirito, che naturalemente si prende da quella incuruatura del braccio, il quale, à guise d’un arco, scocca con violenza nel partire.
The First Guard is more secure than the other two, and makes him master of the his sword more than that which the Second and Third do. Since in it, keeping the right arm soft and bent, it also keeps the point withdrawn so that it would not be very subjected to the opponent’s discretion. The thrusts also occur very quickly from this situation, due to the spirit that is naturally taken from the curvature of the arm, which like a bow, lets fly with violence in the beginning. 
Prima is also useful for helping students ensure that they are moving everything in the proper sequence. For example, if making the finta scorsa, the advancing feint, the student must be careful to minimize the danger to themselves. Marcelli, unlike some of his contemporaries, remarks that one should feint a thrust to thrust, a cut to cut, versus a cut to thrust or thrust to cut. The actions are larger and more prone to counters.
In essence, the student is making an advance-lunge and performing a half-thrust on the advance in coordination with the front foot. The disengage (cavazione) is made as the rear foot moves, and the action finishes with the completion of the extension as one lunges. Importantly, the student must then break measure, moving the head and body first and staying secure behind the weapon, which retracts last. To increase the difficulty, I will sometimes defend, sometimes not, so the student must stay on their game and be vigilant. Normally we change roles as well so that the student can practice the counter to the finta scorsa.
Sample Lesson Plan:
S, from prima: arrests to arm as I. (Instructor) attacks from various lines/guards
Parry riposte: simultaneous, two tempi
●Direct thrust from prima
●Direct thrust from prima parried by I., counter parry-riposte from S.
●Firm-footed, feint direct to inside line; I. parries 4th, S disengages
●Firm-footed, feint direct to inside line; I. parries 4th, S disengages, I. parries and ripostes, S. counter-parries and ripostes
●Finta Scorsa, feint direct to inside line; I. parries 4th, S disengages
●Finta Scorsa, feint direct to inside line; I. parries 4th, S disengages, I. parries and ripostes, S. counter-parries and ripostes
*I. alters guard, S. feints to a different line
●Three point bout (I. sets up situations for S. to work, in real-time, the material of the day)
●Arrest drill or Parry-riposte to close
Prima, Seconda, Terza, Quarta
While keen to share some thoughts on Marcelli’s prima, the process described will work for any of his guards, and indeed, those he advocates when rapier is paired with dagger. The more a student works the actions found within the text, and faces them from various positions, the more robust their game will prove. We are fortunate that the Rules of Fencing is as well-written and clear as it is—I have found it to be a thorough and exciting font of knowledge, as full of technical brilliance as tactical sense. Moreover, spending so much time on this text has made the others in the Neapolitan orbit clearer. Next to Marcelli I like Pallavicini’s work best, but I have found it more opaque in sections; similarities with Marcelli do not necessarily explain those sections in Pallavicini, but they can provide a more solid starting place to attempt to unravel them.
 See Charles Blair, “The Neapolitan School of Fencing: Its Origins and Early Characteristics,” in Acta Periodica Duellatorum 2: 1 (2015): 9-26 [published online 2015 and available at ADP, https://bop.unibe.ch/apd/issue/view/1082]; see especially pages 9-10. See also the brief history by Chris Holzman in his translation of Marcelli’s Rules of Fencing, xi-xiv (similar coverage can be found in his translations of both Pallavicini and Terracusa e Ventura). Blair’s article provides a solid overview, but for guards he focuses on rapier and dagger versus those used for sword alone.
 The images explain it better than I probably can, but French prime sweeps from outside to inside, hand about temple height; Italian prima in Del Frate is much the same, but we see a different parry in some works, mezzocerchio, which is sort of quarta with the blade tip dropped, somewhat akin to French septime.
 As smallsword transformed into foil play, a game all its own, the necessity for the false edge parry of first, which helped keep one farther away from the incoming steel and which set up the offhand parry well, gave way to the faster prime with the true edge. The latter is an all or nothing parry, one that should it fail to sweep the line leaves one horribly open.
 Cf. Marcelli, Regole della Scherma, 64; Holzman, Rules of Fencing, 88. In his note for that passage Chris explains that in “half-fourth, or 3rd in 4th position, the true edge is turned diagonally downward to the inside. What Marcelli calls First Guard, we would probably call a guard of 4th today.” I would add that later smallsword texts that have one hold the blade in fourth, but framed on the right, somewhat like modern French sixte, get close to this, the key difference being the height of the hand and direction of the point.
 Blair, ““The Neapolitan School of Fencing: Its Origins and Early Characteristics,” 9.
Poor Rob Childs will, I’m sure, be sad to discover that he didn’t invent the invincible thrust (exploitation of his “critical angle,” i.e. selecting an open spot and hitting it from the right distance and at the right time…). But, hey, he still has his jump-lunge (oops, no…, that’s a balestra), and his “vertical” and “horizontal” (dang, no, those words first appear in English in the 16th century). Well… he still has is hand-puppet distractor… no, dang again, Joseph Fiennes did that best in “Shakespeare in Love” (Miramax 1998)…
Good-natured teasing aside, for those interested in HEMA’s competitive side time spent with Rob’s videos will help—though he might footnote some of what he shares, the fact is that he provides the “historical” fencer with solid modern technique and ways to exploit the rule-set.
 Purposeful mistakes are not something I have students make with one another. That burden is on me. I don’t advocate having students working on anything that requires one of them to fence poorly on purpose. As the instructor, and as someone whose competitive days are behind him, I have less to worry about. Those actively competing or fighting should learn how to exploit mistakes, but not make them.
 Marcelli, Regole della Scherma, 66; Holzman, Rules of Fencing, 89.