Depends a bit of the period and army. We do know that later armies became more organized.
There are numerous references in the Alexander historians to orders being given by
the bugle (salpinx).6 On numerous occasions a bugler (salpingtes) is stated explicitly as
giving orders to the different units in the army.7 Clearly buglers played an important role
in dispensing instructions in Alexander‘s army.8 They may even have been children as
they often were in British regiments in the 18th and 19th centuries.9
Aides (hyperetai) were used to convey messages between units and to do whatever was
required by the commanding officer. They were the general help for the officer, as both
the ancient and modern terms imply. An aide was indispensable to the commanding
officer in doing the little things so that he could concentrate on the important task at
hand of leading the unit. Wellington relied heavily on his aides during the Peninsular
5 Sekunda‘s assumption that since Ptolemaic Egypt was trying to mimic the army structure of the
Romans they would have adopted every aspect is far from perfect. The size of the phalanx was reduced to match the Roman maniple because it was too cumbersome a unit but this reduction in size did not specifically require three supernumeraries only.
6 Diodorus has seven references to a bugle giving commands in book 17: 17.11.3; 17.25.1; 17.26.5;
17.45.7; 17.68.3; 17.89.1; 17.106.7. Arrian has seven: 1.14.7; 3.18.5; 3.18.7; 4.4.5; 5.24.3; 6.3.2; 7.3.6. Cf. the occurrence of tuba (―trumpet‖) in Curtius: 3.8.23 (Issus); 4.13.22 (Gaugamela); 5.2.7 (the trumpet cannot always be heard above the din); 5.4.17 (at the Persian Gates); 7.1.25 (on the role of the trumpet);
8.1.47 (Cleitus episode, to summon the troops); 8.11.11 (at Aornus); 8.14.10 (the Indians used drums in situations where Macedonians used the trumpet).
7 Arrian: 5.23.7 (x2); 5.24.2 (salpingtai: plu.). Diodorus: 17.86.5. There are many other references to
buglers in historical works. Polybius for example provides 7 references and a further 17 concerning the use of the bugle. Diodorus has 37 other references to buglers and bugles.
8 It is very unlikely that a bugler was not used in the Ptolemaic army because of the necessity for the
passage of clear orders. The lack of reference to one in the papyri occurs because the bugler was not
important enough to be classed even as a junior or non-commissioned officer. The kerux may have taken over the role of the bugler in giving orders but the linguistic origin of the word must mean that originally
there was a herald who used his voice to pass on orders and a bugler who used his bugle.
9 The Chigi Vase shows hoplites marching to flute players.
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