708 REPORT—1899. 
variously stated to last from five to twenty years, and this inquiry was undertaken 
with a view to advising as to the best means of cultivating the land, and also 
to determine the amount of salt deposited, the time required for its removal by 
drainage, and its chemical and physical effects upon the soil constituents, a 
knowledge of which must be of value in the event of future inundations, 
By analysis made after the water had run off, but before an appreciable quan- 
tity of rain had fallen, the soil was found to contain 0:2 per cent of salt, or about 
twenty times the normal quantity. This was insufficient to produce plasmolysis 
of the root-hairs, and it therefore was not directly injurious to growing crops. Nor 
was the condition of the soil then impaired; indeed, the addition of salt to soil 
tends at first to granulate the clay and render it more workable. The immediate 
injury appeared to be chiefly due to the entire destruction of earth-worms. In the 
following season (1898) very few crops were worth harvesting. 
The soils were re-examined this spring (1899). It was found that nine-tenths 
of the salt had been washed down by rain and removed by drainage, and that 
young worms had again made their appearance. The condition of the soil was, 
however, very unsatisfactory, and while on some farms there was promise of fair 
crops, on others the crops had failed. When shaken with water the soil is no 
longer quickly deposited, but remains partially suspended for several weeks, 
evidence that the clay has become gelatinous. This is also shown by the higher 
percentage of water of hydration in the air-dried clay from the flooded soil. The 
retentivity of the soil for water had not become greatly altered, but percolation of 
water through the flooded soil was just half as rapid as through the unflooded. 
These effects appear to be due to the chemical action of the chlorides of the 
sea-water upon the double silicates of the soil. Analysis of the soil shows that 
the percentage of lime, magnesia, potash, and soda had been reduced very mate~ 
rially, and this points to the decomposition of the double silicates, the silicate of 
alumina being left behind in a gelatinous condition. 
It is obvious that for the amelioration of the soil attention must be directed to 
rendering the soil more workable and open, and thus counteracting the effect of 
the gelatinous clay. Ploughing in green crops or the straw of cereal crops and 
long manure, and, above all, thorough fallowing, have already proved to be useful. 
Also, the soil having become impoverished by the action of the salt, dressings of 
lime and potash manures may be required, lime being especially valuable because 
of its known effect in granulating clay. 
5. The Influence of Solvents upon the Optical Activity of Organic Com- 
pounds. By Wi.L1aAmM JACKSON Pope. 
The author traces the variations in the specific rotation of an optically active 
substance dissolved in various solvents to the degree of association of the active 
compound; it is shown that the specific rotation of levotetrahydroquinaldine, a 
highly associated substance, varies from [a]p = — 46° to —118° in different solvents 
owing to the varying degree to which the association factor is changed. On the 
other hand, a substance like levopinene, which is practically nonassociated in the 
pure state, alters its specific rotation very slightly when dissolved in different 
solvents. 
Since the specific rotation is so largely dependent upon the association factor, 
a method can be devised for determining whether a particular optically active 
substance forms a liquid racemic compound with its optical antipodes. Thus pure 
levotetrahydroquinaldine has the specific rotation [a]) = —58:12°, and when 
dissolved in externally compensated tetrahydroquinaldine as solvent its specific 
rotation becomes [a]p = — 58'02°; this practical identity between the two specific 
rotations indicates that externally compensated tetrahydroquinaldine is merely a 
mixture of the two antipodes, each of which retains in the mixture the association 
factor which it possesses in the pure liquid state. Externally compensated tetra- 
hydroquinaldine is, therefore, not a racemic compound, 
