Excuse the quality of these pics i took them on my cell but it shows the "sweating" or as i now think to be more like runny eyes. I think it runs down its leg as it shows in one of the pics because its a little over weight and cannot pull its legs into its shell and the front legs rest on its eyes producing a candling effect driping down the leg which after hours of this can become a whole lot. The temp. today was around 70 with little humidity. But this would also explain why it would happen in all weather conditions because all it is takeing is the front leg to rest on the eye.
