From https://stackoverflow.com/questions/6921275/is-it-possible-to-chain-settimeout-functions-in-javascript

settimeout-chain.js

function delay(fn, t) {
    // private instance variables
    var queue = [], self, timer;
    
    function schedule(fn, t) {
        timer = setTimeout(function() {
            timer = null;
            fn();
            if (queue.length) {
                var item = queue.shift();
                schedule(item.fn, item.t);
            }
        }, t);            
    }
    self = {
        delay: function(fn, t) {
            // if already queuing things or running a timer, 
            //   then just add to the queue
            if (queue.length || timer) {
                queue.push({fn: fn, t: t});
            } else {
                // no queue or timer yet, so schedule the timer
                schedule(fn, t);
            }
            return self;
        },
        cancel: function() {
            clearTimeout(timer);
            queue = [];
        }
    };
    return self.delay(fn, t);
}

function log1() {
    log("Message 1");
}
function log2() {
    log("Message 2");
}
function log3() {
    log("Message 3");
}

var d = delay(log1, 500)
    .delay(log2, 700)
    .delay(log3, 600)