When you are dealing with objects such as charts you are better off witha
collection than an array... Try something like this...
Sub test()
Dim colCharts As Collection
Dim cht As ChartObject
Set colCharts = New Collection
colCharts.Add Sheet1.ChartObjects(1), "Chart1"
colCharts.Add Sheet2.ChartObjects(1), "Chart2"
For Each cht In colCharts
MsgBox cht.Name
Next cht
End Sub