Ordering in Firebase for large amounts of data

Question

I have relatively large amount of data in firebase here: https://nysenate.firebaseio.com/

The question is how do I get the results in order.

For example, for a firebase of 100K objects, I'd like to get the first 10 after the entire set is sorted by publishedDateTime.

But if you look at the results, it does not seem to be sorted at all. In fact, I can't really tell what the order is.

(these are all public read firebases so you can test using the same curl command)

$ curl 'https://nysenate.firebaseio.com/bills.json?orderBy="publishedDateTime"&limitToFirst=10&print=pretty' |grep publishedDateTime
   "publishedDateTime" : "2015-06-05T09:16:05",
   "publishedDateTime" : "2015-06-05T09:16:05",
   "publishedDateTime" : "2015-06-05T09:21:05",
   "publishedDateTime" : "2015-06-05T09:21:05",
   "publishedDateTime" : "2015-06-05T11:21:11",
   "publishedDateTime" : "2015-06-05T10:36:09",
   "publishedDateTime" : "2015-06-05T13:56:18",
   "publishedDateTime" : "2015-06-05T11:16:11",
   "publishedDateTime" : "2015-06-05T13:51:18",
   "publishedDateTime" : "2015-06-05T13:46:18",

It seems to work for small amounts of data: (6 objects) using one of the demonstration firebases.

$ curl 'https://dinosaur-facts.firebaseio.com/dinosaurs.json?orderBy="height"&limitToFirst=10&print=pretty' |grep height
            "height" : 0.6,
            "height" : 0.6,
            "height" : 2.1,
            "height" : 3,
            "height" : 4,
            "height" : 25,