SHOWN BY THEEMOMETERg. 37 



With regard to tliese thermometer changes, there have been 

 found some very remarkable coincidences which should also be 

 placed on record. The first jump in the thermometer was during 

 the 27th of February. On that day at 2*30 p.m., we were visited 

 by a small tidal wave, the result, it would seem, of earthquakes 

 in New Zealand. 



From 7th to 17th April we have the next remarkable part of 

 the thermometer curve, and we have also many small tidal waves 

 recorded about the same time. 



On the 3rd of May we have the next conspicuous point in 

 the curve, and on that day at 11'30 p.m., another tidal wave is 

 recorded in Sydney and Newcastle, with many minor disturbances 

 about the same time ; and on the 7th of May we have the second 

 in magnitude. On that day, at 6'45 p.m., another tidal wave 

 reached Sydney, the result of earthquakes in New Zealand. 



Again, on 21st of May, we have another feature in the 

 thermometer curve, and another tidal wave recorded in Sydney 

 harbour at 11*30 p.m. Are these coincidences accidental, or are 

 they consequences of some impulse affecting all alike ? 



In the diagram the straight line represents the readings of the 

 standard thermometer, reduced to a straight line. The curved line 

 shows the difference between the dry bulb and the standard. At 

 9 a.m. on each day the gradual decrease in the difference shown 

 day after day in so marked a manner is evident in all the 

 readings, the differences being less at night than in the morning ; 

 showing a steady decrease in the gas or other substance in the 

 thermometer which produced the difference. 



Sydney Observatory, 7th June, 187G. 



