OBSERVATIONS TAKEN IN INDIA. 
315 
P.M., the barometer was 30’121 ; at 12^ 41"*, instead of continuing’ to fall, it had risen 
to 30’125, but then changed; and at2**41'"it was30’104, and fell regularly till 3^ 41"* 
A.M., when it was at its minimum, 30’089. On the 2 1st of September, in 1843, the mini- 
mum A.M. nocturnal tide occurred at 1** 41*" a.m. instead of 3** 41'**, at which hour it 
took place on the morning of the 22nd ; the interval, therefore, between the minimum 
of this A.M. nocturnal tide and the maximum of the 9 — 10 morning tide, was seven 
hours, the maximum occurring at 8^ 41*", a very rare instance of the continued flow 
of this A.M, tide, which usually runs its course within four or five hours, and on rare 
occasions in three hours ; the change of pressure, however, was only equal to O’l 14, 
from 29‘763 to 29’877- In 1844 there is hut one instance of irregularity within the 
prescribed hours. On the 22nd of September, at 12'* 41*" a.m,, the barometer stood at 
29’820 ; at l'* 41*" it had fallen as usual to 29’808, but at 2** 41*” it had risen to 29’819; 
at 3** 41*" to 29’833 ; but at 4^* 41*" it had fallen to 29’832, and then continued regular. 
In 1845 there is also only a solitary instance on the 21st of March. At 7'‘ 41"* a.m. 
the barometer stood at 29 933; at 8** 41"* it had fallen, instead of rising, to 29*932, 
but at 9^* 41*“ resumed its usual course. It will be remarked that at Madras there is 
not a single instance of irregularity in four years in the fall of the great diurnal tide 
from 9 — 10 a.m. to 4 — 5 p.m., and the instances of irregularities in the other tides only 
serve to prove that the laws are not without exceptions. From the above comparisons 
it is seen that the irregular movements in the tides were not common to Dodabetta 
and Madras at simultaneous periods of time, nor at proximate periods of time. The 
irregularities in the intervals of the different tides are numerous, as are also the in- 
stances of stationary periods in which the atmosphere appears to be quiescent from 
one to two hours. It now remains to notice the deviations from the usual laws at Bom- 
bay, as recorded by Dr. Buist in his Bombay hourly observations for 1843 and 1844, 
On the 21st of January, at 3 a.m., the barometer stood at 29’864, at 4 a.m. at 29’865; 
but at 5 A.M., instead of continuing to rise, it had fallen to 29’863, and continued to 
fall until 6 a.m., when it stood at 29 856; at 7 a.m. it resumed its usual course, and con- 
tinued to rise until the maximum hour. At Madras, on the same day, making allowance 
for the difference of longitude, nothing of the hind occurred. At Bombay, on the 21st 
of March, at 1 1 p.m., the barometer stood at 29’688; but at midnight, instead of con- 
tinuing to fall, it had risen to 29’699, and it was only at 1 a.m. it resumed its ebb. 
There was nothing of the hind at Madras, where the maximum, 29’86I, was attained 
at 10** 41*" with the ordinary regularity. On the 22nd of May, at Bombay, there were 
irregularities in all the tides, a thing so unusual, and not occurring at all on the 20th 
or 23rd of May, as to render the table apocryphal, either from error in the record or 
in the lithography ; the a.m. falling tide stops at 2 a.m., then rises to 8 a.m., falls to 
9 A.M., and then rises to 10 a.m,, its maximum, however, being at 8 a.m. From 4 p.m, 
the tide as usual rises to 6 p.m., then falls to 8 p.m., and afterwards proceeds to attain 
its maximum at 11 p.m. Something similar occurs between 1 and 5 a.m, on the 21st 
of June, but not on the 22nd. Nothing of the hind occurs at Madras, either on the 
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