Edit in JSFiddle

function logMsg(str, noBreak) {
    var msg = $('#message');
    msg.append(str);
    if (!noBreak) // if noBreak is asigned a value (any value), <br /> won't be output
        msg.append('<br />');
}

function Chessman (name, location, isAbroad) {
    this.name = name;
    this.location = location;
    this.isAbroad = isAbroad;
    this.color = 'Black';
}

Chessman.prototype = {
    constructor: Chessman,
    move: function () {
        logMsg(this.name + ' moved.');
    }
}

var Soldier = new Chessman ('Soldier', {}, false);
Soldier.color='Red';
logMsg(Soldier.color);
Soldier.move();
var Knight = new Chessman ('Knight', {}, false);
Knight.color='Black';
logMsg(Knight.color);
Knight.move();
<div id="message" />
body {
    font-family: Verdana, Arial;
    font-size: 1.1em;
}