diff --git a/lib/history.js b/lib/history.js
index b238271..a60123e 100644
--- a/lib/history.js
+++ b/lib/history.js
@@ -276,14 +276,14 @@ History.prototype.prevMaxBlock = function(number)
 
 History.prototype.bestBlock = function()
 {
-	return _.max(this._items, 'height');
+	return _.maxBy(this._items, 'height');
 }
 
 History.prototype.bestBlockNumber = function()
 {
 	var best = this.bestBlock();
 
-	if( !_.isUndefined(best.height) )
+	if( !_.isUndefined(best) && !_.isUndefined(best.height) )
 		return best.height;
 
 	return 0;
@@ -291,14 +291,14 @@ History.prototype.bestBlockNumber = function()
 
 History.prototype.worstBlock = function()
 {
-	return _.min(this._items, 'height');
+	return _.minBy(this._items, 'height');
 }
 
 History.prototype.worstBlockNumber = function(trusted)
 {
 	var worst = this.worstBlock();
 
-	if( !_.isUndefined(worst.height) )
+	if( !_.isUndefined(worst) && !_.isUndefined(worst.height) )
 		return worst.height;
 
 	return 0;
@@ -335,8 +335,7 @@ History.prototype.getNodePropagation = function(id)
 				}
 			}
 		})
-		.reverse()
-		.value();
+		.reverse();
 
 	return propagation;
 }