K i did a quick civilopedia text of the MKIV tank It should work i have no idea why it wouldn't but here it is just add it to ../civilization III/text/civilopedia or whatever your folder is
then "find" Tank and paste this into the civilopedia text before the tank civilopedia or wherever you want then just add #PRTO_MKIV to you .Bic folder also you will want a pediaicon which i will work on.


here it is...

#PRTO_MKIV
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^[MKIV] tanks are slow-moving defensive units that have same about same attack capabilites of cavalry
but only one movement. Also the MKIV has a higher defensive value than most units of its time.
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^A city must have both $LINK<oil=GOOD_Oil> in its $LINK<Strategic
Resource=GCON_ResourcesS> box to build MKIV tanks.
#DESC_PRTO_MKIV
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^The concept of armor protection dates from antiquity. By the 5th century BC Greek warriors, and sometimes their horses, wore armor. Florentine artist and scientist Leonardo da Vinci designed a crank-operated covered chariot in 1482, but development of an effective, track-laying armored vehicle was only possible after the invention of the internal-combustion engine.

During World War I (1914-1918) the British developed and used the first armored track-laying vehicles. To maintain secrecy, the vehicles were shipped to the battle zone in crates marked "tanks," hence the origin of the name. The first battle in which these tanks were employed was the Battle of the Somme, on September 15, 1916, when the British used forty-nine tanks 
with disappointing results. Little more than a year later, however, in November 1917, 400 British tanks penetrated German lines near Cambrai, capturing 8000 of the enemy and 100 guns. Thus starting the evolution of what was to be the modern tank.

