,26o THE ANTIQUITY OF MAN IN TASMANIA. 



Others, have noticed that the tronattas are restricted to 

 the surface ; none are in the subsoil, however much I 

 searched for them. The number of specimens on the 

 surface is never ver}- large (2), and this proves that the 

 camping-grounds could not have been^ used for any 

 length of time. In fact, the whole appearance of the 

 camping-grounds proves them to be of quite a modern 

 date ; not a single one has been found which could claim 

 any antiquit}- . 



Even if my figures are not accepted, there remains 

 at least one unshakeable fact — the immigration of man 

 into Tasmania must have' taken place in a geologically 

 very recent period, viz., after the young volcanic period, 

 but it must have taken place before the appearance of 



this view is borne out by the facts. A short calculation will 

 show us that enormous shell heaps must collect in comparatively 

 short time. 



According to the best authenticated figures the total popu- 

 lation of Tasmania was 2,000 souls in 1803. Now, let us assume 

 that each individual consumed 50 oysters, including mutton fish, 

 mussels, etc., per day — surely not too great an allowance. There- 

 fore, 100,000 shell fish of sorts were consumed per day, or three 

 million per month, equal in round figures to 2>^ millions per year. 



According to my estimate of time 180,000 million shell fish 

 would have been consumed in 5,000 years, and 254,000 million in 

 7,000 years Assuming that the valves did not weigh more than 

 two ounces, the weight of these shells would be 13.2 million tons 

 and 18.8 million tons respectively. 



Now, let us assume that in the average each oyster or 

 haliotis shell measures 4x3x1 inch — a very moderate estimate 

 of size; therefore 144, say 150 shells, would go to the cubic foot, 

 and the above numbers would be equal to 1,200 million and 

 1,693 niillion cubic feet respectively, which would cover a tract 

 of land measuring half-a-mile in width and 10 feet deep for 10 

 or 16 miles in length, according to the lower or higher figure. 



These figures prove conclusively what enormous shell heaps 

 gather in such a short time as 5,000 or 7,000 years. If Tasmania 

 had been inhabited for any longer period, say 50,000 or 100,000 

 years, the shell heaps would be much more extensive than they 

 actually are. According to the above calculations, 12,000 million 

 cubic feet of shells, weighing 92.4 million tons, and covering a 

 strip of land half-a-mile in width and 10 feet deep for 20 miles 

 in length, would have been left behind, an area which would in- 

 crease to 40 miles in length were the time to be 100.000 years. 



From what I have seen of the shell heaps their total bulk 

 would not come anywhere near 1,200 or 1,700 million cubic feet, 

 much less to 12,000 or 24,000 million cubic feet. The shell heaps, 

 large as they appear, are therefore rather a proof in favour of a 

 small than of a great antiquity of man in Tasmania. 



(2) Except, of course, in the quarries. 



