Roman helmets: Imperial Gallic/Italic and Ridge - comparisons and sources

[CaesarAugustus]

Nope, we were discussing about quality of the helmets.

Define "Quality"

You should ask to Goldsworthy, but I can reply with an acceptable margin of error and we can improve the definition.

First of all, we have to consider requirements and constraints. For the constraints, the helmet has not to be heavy, otherwise is not practical and, even worse, in case of impact will create damages to the neck and to the head. For the requirements, Romans gave massive importance to the possibility to listen and to the visual field. Otherwise, a Corinthian helmet would be hardly beatable for the period.

Then, there are aesthetic aspects. For example coppery appearance, gems, trinkets, and generally the shape. These are really relative, for example as a matter of shape I prefer the Attic helmet. And we could discuss about the quality of the finishes, but this is not what we are discussing in this topic.

So, kept in mind the requirements and constraints, finally we move to the real factors that can establish the quality of the helmet.

As a matter of fact, the helmet purpose is understood as head protection, against penetration and shock/brain injuries. Thus, the purpose of protective helmets is to prevent head injury by decreasing the amount of impact energy that reaches the head, reducing the severity or probability of injury. So, the quality of the helmet is given by the ability to reduce the severity or probability of injury.

Besides resistance to penetration, the helmet is the initial shock absorber. We can highlight as follow the helmet responsabilities:
- spreading the impact load over a large area of the helmet, therefore reducing the concentrated stresses during an impact that
reaches the head and increasing the amount of energy absorbed, by having a larger area of effective energy absorbing liner;

- prevent helmet penetration by pointed or a sharp object that might otherwise puncture/penetrate the skull;

- absorbing the initial shock in an impact.



We can consider that ridged and italic cover more or less the same area (we can ignore for a while that the italic offer more protection for the neck), so, more or less, the defense against the penetration is the same. But, there is a little problem near the ridge. The ridged is made by flanked pieces, fixed by rivets. This means that near the ridge there is discontinuity and the impact is not distributed equally in different direction. So, the possibility that the metal is bent between rivets is higher than the probability to bend the metal of an italic helmet.

And, problem related, this discontinuity obstruct a correct spread of the shock on a larger area. One think is the ability of an italic helmet to spread the blow on the entire helmet surface, other is the the flanked pieces that circumscribe the impact area on a smaller area, thus reducing the amount of energy absorbed, that is leaving a greater energy to reach the skull, and finally the brain.

For these reasons, today the helmet are generally monoblock, the continuity of the medium, the helmet, allows to better distribute the impact of a blow, being it composite or metal. This considerations are taken from Design And Analysis Of Industrial Helmet and Performance Analysis of Motor Cycle Helmet under Static and Dynamic Loading, which theory can be applied to our topic without any problem.



So, considered our requeriments and constraint, we can safely agree with Goldsworthy. Ridge helmets were not of the quality of earlier types.



I hope this definition satisfies you (even if it does not reflect your previous ideas)