try {
            // Construct lava
            Class blockFlowingLavaClass = Blocks.flowing_lava.getClass().getSuperclass();
            Field blockFlowingLavaIconField = blockFlowingLavaClass.getDeclaredField("field_149806_a");
            blockFlowingLavaIconField.setAccessible(true);
            Object blockFlowingLavaIconObject = blockFlowingLavaIconField.get(Blocks.flowing_lava);
            IIcon[] blockFlowingLavaIcon = (IIcon[]) blockFlowingLavaIconObject;
            // Construct water
            Class blockFlowingWaterClass = Blocks.flowing_water.getClass().getSuperclass();
            Field blockFlowingWaterIconField = blockFlowingWaterClass.getDeclaredField("field_149806_a");
            blockFlowingWaterIconField.setAccessible(true);
            Object blockFlowingWaterIconObject = blockFlowingWaterIconField.get(Blocks.flowing_water);
            IIcon[] blockFlowingWaterIcon = (IIcon[]) blockFlowingWaterIconObject;

            // Set the fields back
            blockFlowingLavaIconField.set(Blocks.flowing_lava, blockFlowingWaterIcon);
            blockFlowingWaterIconField.set(Blocks.flowing_water, blockFlowingLavaIcon);
        } catch (Exception e) {
            e.printStackTrace();
        }