diff --git a/core/modules/startup.js b/core/modules/startup.js
index 9a15d3dd6..d333f73a2 100644
--- a/core/modules/startup.js
+++ b/core/modules/startup.js
@@ -75,8 +75,8 @@ exports.startup = function() {
 			story.tiddlers[t] = {title: defaultTiddlers[t]};
 			history.stack[defaultTiddlers.length - t - 1] = {title: defaultTiddlers[t], fromTitle: defaultTiddlers[t+1]};
 		}
-		$tw.wiki.addTiddler(new $tw.Tiddler({title: storyTitle,type: "application/json", text: JSON.stringify(story)}));
-		$tw.wiki.addTiddler(new $tw.Tiddler({title: historyTitle,type: "application/json", text: JSON.stringify(history)}));
+		$tw.wiki.setTiddlerData(storyTitle,story);
+		$tw.wiki.setTiddlerData(historyTitle,history);
 		// If we're being viewed on a data: URI then give instructions for how to save
 		if(document.location.protocol === "data:") {
 			var event = document.createEvent("Event");