|
When trunnions were first invented c1450 they were placed with their axis at right angles to the axis of the bore, the logical place for them one would have thought. Then someone noted that when a gun was fired it tended to rock up and down as in those days it had no elevating gear to hold it in place, or possibly breech preponderance was insufficient. Some mathematical genius thereupon calculated that if the axis of the trunnions was placed at right angles to the bottom of the bore, forces generated by the gun firing would hold the breech down. How right he was. Not only were breeches well and truly held down, for the next 300 years Gunners were plagued by cracked or broken trails on field pieces or beds on garrison or naval guns. Furthermore, the same forces acting on the wedge-shaped quoin used for applying elevation or depression often caused it to be violently ejected to the rear, to the discomfort of any hapless Gunner who happened to be in its way!
The same genius, to bolster his case, also claimed that trunnions with their axis aligned with the bottom of the bore formed a stronger union with the piece, a claim refuted by John Muller in the same treatise already mentioned. Muller's recommendation that trunnions be returned to their original position was ignored, one of the reasons which led him to remark, 'Our veneration for old customs is so great that whoever attempts to make any change is looked upon with contempt, let his reason be ever so plain and good'. Not until the middle of the 19th century was the Board of Ordnance finally convinced that the best place for trunnions was where the gunmakers of 1450 put them! |
|
WL Ruffell Issue 88 December 1995 |
previous | index | next |
History Home Page | Old Comrades' Home Page
Send suggestions or comments to the Webmaster
Page last updated: December 7, 1998