12G TllK 0( (JLUKKNCK 01- (iKIANTlC MAUSUl'lALS IN TASMANIA. 



cn which the peat rests, is below sea level, and this would 

 account in some way for the sluggishness of the fall. When 

 drained this peat forms a rich agricultural scil, and it 

 is during the course of such drainage works that the 

 remains were discovered on Mr. Lovett's faiTn. 



The fertility of the soil can be judged by the fine tim- 

 ber that grows on the swamp, but a great deal of clearing 

 and, above all. draining will have to be done before the 

 soil can be used to its full extent. 



The clearing has revealed a very peculiar feature of the 

 surface. Everywhere, where the bush is lighter, small coni- 

 cal mounds, rising abn.iptly from the surface, will be 

 noticed. Generally these are not of great height ; the high- 

 est I saw was about 30ft., but the majority are not more 

 than lOft- high. These mounds look like little volcanoes, 

 and the likeness appears greater still, as on the top there 

 is a crater-like opening filled with water, in which gas 

 bubbles constantly rise. The water flows over the edge, 

 down the slope, and the immediate neighbourhood of such 

 a mound is particularly swampy. In order to prevent this, 

 and to regulate the outflow, several of these mounds have 

 been opened by a trench, extending right into the centre. 

 This trench has not only revealed the existence of a pipe, 

 reaching from the' bottom to the top of the mound, but it 

 also permitted its structure to be studied We see that the 

 mounds consist of body of peat, which rises above the gene- 

 ral surface, and dips from the centre in all directions. On 

 the surface of this cone layers of calcareous tuffa are ob- 

 sei-ved, while layers of fine mud, containing numei'ous shells 

 of fresh water mollusca, are seen to be interstratified with 

 the peat. 



There is only one explanation to account for the exists 

 ence of these cones, the vegetabilic matter in the depth of 

 the swamp is still decaying, and as the result of the 

 decomposition gases are liberated. These gases rise and 

 lift the peat till it assumes the shape of a bubble, which 

 eventually bursts. The gases have now a free exit, but the 

 pressure is still sufficient to make the water rise to the 

 top. where it flows over. 



It was, of coui'se, of some importance to ascertain the 

 nature of the gas rising in the water, whether it be sulphu- 

 retted hydrogen, a hydro-carbon, or carbonic acid. Sulphu- 

 retted hydrogen is easily detected by its unpleasant smell. 

 The entii'e absence of such smell proved that the gas could 



