VOL. XL.] PHILOSOPHICAL TRANSACTIONS. 201 



do not get home bj- such a time, or pass such rivers, the floods will be so great, 

 as not only to prevent me, but endanger my life : and perhaps here is a man's 

 fortune saved, nay his life, merely from the indications of the barometer ; and 

 he who reckons this nothing, deserves neither. 



The greatest storm that has been in our days, was Jan. 8, 1734-5. On the 

 5th the mercury began to fall, and on the 8th was a 10th below 28 inches; 

 which has not been seen in this age, or perhaps since Torricelli's time ; thence 

 I could plainly indicate, that it would be the greatest flood we ever heard of, or 

 the greatest storm we ever felt ; the latter of which it proved. 



Some Rules and Observations for fore-knowing the Weather, by the rising a7id 

 falling of the Mercury. — Though rising always presages fair, and falling foul 

 weather, yet there are several difficulties and niceties in making a true judg- 

 ment from them, and herein consists the chief part of the art. 



We need not recount the several observations made by Dr. Halley, Dr. Beal, 

 Dr. Derham, Mr. Patrick, and others, though they are most of them appli- 

 cable to this improved diagonal barometer, as they are in so many hands, and 

 in most authors on the subject, and because Mr. B. has collected them, in 

 order to be made public, at the request of the improver of the barometer, Mr. 

 Orme, and for his use; which ^me time since were put into the hands of Dr. 

 Desaguliers, who is acquainted with Mr. Orme and his glasses. Mr. B. only 

 inserts here some few observations, which may be called rules, as he has 

 deduced them from time to time, in using Mr. Qrme's glasses, and keeping a 

 register of the weather. 



Rules and observations for the improved diagonal barometer. — 1. This baro- 

 meter very rarely foretels thunder, seldom falling at all before it, which Mr. 

 Patrick observes others do. 



2. In serene and hot weather, when the mercury is high and rising, and you 

 have all the possible certainty of fair weather the next day, and if there happen 

 to fall great showers, you may conclude they have been driven on you by 

 thunder, though you have heard nothing of it. 



' 3. When the mercury is pretty high, and has fallen to foretel rain, and it 

 rises again before the rain comes; it indicates there will be but little of it. 



4. If the mercury continues falling while it rains, it shows it will rain the 

 next day. 



5. In fair weather, when the mercury has continued high or rising, if it falls 

 a little to-day about noon, and towards the evening rises again, you must expect 

 a single shower the latter part of the next day, or perhaps by noon, and then 

 fair weather again forward. 



■ '6. When the mercury rises gradually, about half a 10th perpendicular, and 



VOL. VIII. D D 



