❧ observations upon the calendar glass.  
THe property of this water is to ascend with cold, and descend with heat, upon the least and every change of the outward air, certainly.  
Secondly, the sudden falling of the water is a certain sign of rain; for example, if the water fall a degree or two in seven or eight hours, it will surely rain then presently, or within ten or twelve hours after.  
Thirdly, if the water fall in the night season, it will surely rain, for example; if the water be fallen any lower in the morning at sunrising, than it was over night after sunsetting, it will surely rain that day following before midnight: Probatum est.  
Fourthly, you must mark at what degree the water standeth when it first beginneth to fall against rain; for until it riseth up again to the same degree from whence it first fell against rain, the weather will still be rainy more or less: Probatum est.  
Fiftly, so long as the water continueth certain at any one degree whatsoever, so long the weather will continue certain at the same stay that it is then at, whether it be fair or foul, frost or rain; but if the water rise or fall a degree or two, and so standeth, the weather will presently change: Probatum est.  
Sixtly, Note that at the figures of 1. 2. and 3. is the extreme heat of the Summer.  
At 4. and 5. not so hot,  
At 6. more temperate,  
At 7 is a degree more hot than cold,  
At 8. is the medium, or very temperate,  
At 9 is a degree more cold than hot,  
At 10. is a frost certainly,  
At 11. and 12. harder frost,  
At 13. and 14. store of Ice upon the Thames at London, and other rivers in the country,  
At 15. boats cannot pass for Ice,  
At 16. men may go over the Thames on the Ice on foot, Porbatum est.  
Seventhly, Note that so long as the water continueth above the figure of 10. so long the frost will last, but if the water fall below the figure of 10. and so standeth, the frost will break certainly.  
Eightly, Note that in the time of frost, the water standing above the figures o● 11. or 12. the sudden falling of the water a degree or two, is a certain sign of Snow, or sleeky weather certainly.  
You may also know the temperature of your body, whether your body be hotter or colder, more at one time then at another, by holding your hand upon the head of the glass.  
These rules are all certain and truly proved by John Slade dwelling at the blue Bell at Lambeth.