Geology and Natural History. 157 



of food. It yields an average yearly revenue of £23,000. Another 

 less valuable industry is that of che oyster which yields about 

 £8000 annually. The food fishes also include a large number of 

 recognized value, and others not yet utilized. The number of 

 species of Queensland fish is stated to be nearly 900. 



It is not possible to give an adequate impression of the wide 

 general and scientific interest of Mr. Saville Kent's beautiful work. 

 The geological student would derive from its illustrations an 

 idea of the luxuriant growth of limestone-making seas that would 

 be like a revelation to him ; and to many the views would appear 

 the more marvelous that all this growth is going on in shallow 

 waters. 



7. Amount of water in the soil after a period of severe 

 drought. — M. Reiset (Comptes rendus, May 23, 1893) communi- 

 cates some interesting facts relative to the effect of certain forms 

 of vegetation upon very dry soil. The data are derived from 

 observations made during the year 1887 when the rainfall was 

 5*87 meters instead of over 9*; the average. In June there fell 

 only '028 instead of -073, and in July barely -033 against the 

 usual amount of 0'72. From the 4th of June to the 23d of July 

 no rain fell. On the 2d of August, after a second period of 

 drought, five samples of earth were taken from a depth of -15 to 

 •25 below the surface, each containing from 8 to 10 kg. of soil, 

 and each was quickly powdered, sifted to take out the pebbles, 

 and placed in a glass-stoppered bottle. Two samples of 10 grams 

 each were subjected to a temperature of 110° to 120° C. with the 

 following results. 



Percentage of water. 



1. Under clover _ 4*84 



2. " wheat, about ripe 3'78 



3 " scorched herbage 4*70 



4. " wheat in full growth 5*04 



5. " scorched lawn 7*84 



6. " wheat nearly ripe ._ _.. 3*81 



Another observation eleven days later was made on the lawn- 

 soil, no rain having fallen in the mean time. There was found 

 a percentage of 6-80. 



A second series of experiments was tried on soil, on the 9th of 

 August, a good crop of wheat having been removed from it on 

 the day before. 



Percentage of water. 



Surface, at the roots of the wheat 1*22 



At a depth of 0-20 slightly gravelly _ .. 4*95 



it a . 4 q u a ___ 9 . 47 



" " 0-60redelay. 14-12 



" " 0*80 " 2T81 



" " 1-00 sub-soil red clay 26*18 



Still another observation, on soil from which vetch and oats 

 cultivated for fodder had been removed ten days before. 



