:The 1981 and '82 Guinness editions (perhaps others aswell) gave quite detailed – and much more plausable – information on the subject: carapace length 165 cm (65 in), carapace height 89 cm (35 in), total length 244 cm (96 in) and estimated weight 852 kg (1,875 lb) for a specimen found in 1923. Compared to the largest Galápagos tortoise individual, named Goliath (carapace length 137 cm/54 in, width 103 cm/40½ in, height 69 cm/27 in, weight 417 kg/420 lb), it was more heavily built: a 165 cm carapace would suggest a weight of 728 kg (1,605 lb) with Goliath's proportions. Also note that the largest known chelonian Archelon ischyros is usually estimated at 2,000 kg (4,500 lb), so 2.5 to 4 tonnes is just absurdly high. 
 :One must take care not to confuse total lengths with carapace lengths, for these yield radically different results when estimating weights. The carapace of T. atlas seems to account for some 2/3 of its total length – I wonder if this applies to the Galápagos tortoise too: if so, then Goliath should be about 203 cm (80 in) long. That 1.80 m height seems a bit odd, but I suppose it could have extended its neck that much from the ground. 
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