495 
hetwelk men van Burss Barror’s wet trekken kan, veel ver- 
minderd en volgens den heer Scorr zal men geen voldoende 
waarschuwing van een storm krijgen, indien men op den ba- 
rometer alleen let (*). Men moet op vele andere zaken, win- 
(*) Onlangs is in het Tijdschrift der Schotsche Meteorologische Vereeniging 
(het nommer voor Januari en April 1873) een brief van den heer Buys Bar- 
LoT gepubliceerd, waarin deze een kort overzicht geeft van het gebruik, dat 
men van de door hem gevonden wet bij wêervoorspelling, meer in het bij- 
zonder in Nederland, maken kan. 
Nadat de inrichting der tafels van het Ned. meteorologisch jaarboek, waar- 
in de waarnemingen voorkomen, die den samenhang tusschen den barome- 
terstand en den wind moeten aangeven, uiteengezet is, zegt de heer Buy 
Barror het volgende. 
‚From a careful examination of the large mass of details there collected, 
the following results will appear: 
1. As regards the relation of the wind to atmospheric pressure, the 
direction of the wind obeys the law of the relation better than the force 
does, nearly without exeption, if pressures be higher in the south than in 
the north, winds in such cases being westerly. On the other hand, easterly 
winds do not arise so easily as westerly winds; — they not only do not 
follow the gradients so closely, but if the difference between the gradients 
be not considerable, they (the easterly wiuds) do not follow at all. 
2. Polar winds have a different gradient from equatorial winds. Thus, 
if atmospherie pressure be higher in the north than in the south, a steeper 
gradient is required to give a pressure of 6 Ibs. on the square foot, than 
would be required when atmospheric pressure is higher in the south than 
in the north to give a westerly wind of 6 Ibs. to the square foot. 
9. The east and north-east winds are not only weaker with respect 
to the steepness of the gradients which have been formed, but they follow 
the formation of the gradients after a much longer interval of time than 
happens in the case of the north-west wind. It, indeed, frequently occurs, 
that after a pretty steep gradient has been formed, from which an easterly 
wind might be looked for, rain follows, and not a very strong easterly wind. 
In general, the north-west wind is a weak point in my predictions of wea- 
ther, owing to the quickness and force with which these winds spring up 
after the barometric indications have appeared. 
4, The converse of this does not hold good, viz. a strong wind does not 
arise when there has been neither a steep gradient preceding it nor a great 
difference between two consecutive gradients. 
5. If there has been a strong wind after a steep barometric gradient, as, 
