The first was that there was an almost total absence of reliable observations.

Between 1866 and 1878 no reliable observations of the hypothetical planet were made.

These are merely the more "reliable observations" of alleged intra-Mercurial planets.

This proved to be a bad idea, because the roof was made of wood, which transfers too many vibrations to make reliable and precise observations.

Some Mira variables (including Mira itself) have reliable observations stretching back well over a century.

Gulliver's reliable observations in Part I is one such device.

Meanwhile, national weather agencies had begun to compile masses of reliable observations of temperature, rainfall, and the like.

There are few reliable observations of infanticide in leopards but new males entering the population are likely to kill existing cubs.

As a Warrior, I was more concerned with reliable observation than with explanation.

An artificial environment makes reliable observation of non-defensive behavior difficult.