Owing to observational difficulties, the exact measure of success attained is a little difficult to gauge, but it seems fairly certain that raindrops usually carry a charge.
All along the base of the highlands, from Khojent to Vyernyi, earthquakes are frequent; 3 but their effects lie beyond the scope of our observational methods.
It became fairly certain, however, that theory had outrun observational work, and that the latter must again receive renewed attention.
In the southern hemisphere there is comparatively little inhabited land in high latitudes and observational data are few; thus little is known as to how the frequency varies with latitude and longitude.
The invention of the portable electrometer and the water-dropping electrograph by Lord Kelvin in the middle of the 19th century, and the greater definiteness thus introduced into observational results, were notable events.
Cousin was observational and generalizing rather than analytic and discriminating.
Before considering observational data, it is expedient to mention various sources of uncertainty.
Whilst no small amount of observational work has been done in these new branches of atmospheric electricity, the science has still not developed to a considerable extent beyond preliminary stages.
Now that psychology, or the observational and experimental study of mind, may be said to have been definitively included among the positive sciences, there is not even the apparent ground which once existed for such an idea.
The observational method applied to consciousness gives us the science of psychology.