These early weapons were known as 17/25-pounders and given the codename Pheasant.

"But at a guess I'd say that the aliens are using a variation of their earlier weapon."

Metal weapons might have been better than earlier weapons.

The spherical Gurney equation has applications in early nuclear weapons design.

In early antitank weapons, copper was used as a liner material.

Fire was the basis of all early thermal weapons.

This became possible with the superseding of earlier weapons like the highly inaccurate musket.

These early modern weapons having been introduced to the two kingdoms by the Portuguese sometime earlier.

The early nuclear weapons were large, complex and cumbersome.

Tackling the problem posed by earlier nuclear weapons is a major step in this respect.