1884.] P. Chambers — Winter Bains of Northern India. 171 



It is well known, however, that cyclonic disturbances do cross 

 mountainous districts, as, for instance, the Rocky Mountains of America, 

 and the Western Ghats of India, although, in doing so, they appear to 

 suffer a considerable amount of disintegration. 



It cannot be assumed, therefore, that they never cross Afghanistan 

 or the northern and more elevated portions of Beluchistan, much less 

 that they never cross the southern and lower parts of the latter state or 

 never come to us from any westerly direction. The American charto- 

 grapher has marked two winter storms as having crossed the north- 

 western frontier of India during their passage eastwards. Mr. Blanford 

 says, this can only be a guess in the dark, and to a certain extent he is 

 correct, but the explanation is very easy. It is exactly the same as that 

 which accounts for the dotted isobaric lines, drawn across the Bay of 

 Bengal on most of the charts of the Indian Meteorological Department. 

 All such lines are more or less hypothetical, and the American charto- 

 grapher has acknowledged that his Indian storm tracks are, to some 

 extent, doubtful, by drawing them in dotted lines. Guided, no doubt, 

 by his knowledge of the general direction of storm tracks, and having 

 traced a track, by means of actual observations, from one place to 

 another, he applies the principle of continuity and extends the track over 

 regions where observations are missing, indicating the fact of his having 

 done so by dotting his lines. Such lines merely indicate probabilities 

 of a greater or less weight, not certainties, and the fact is well under- 

 stood by all meteorologists. 



Mr. Blanford states that he has examined the registers of the 

 Quetta Observatory, and that, with the exception of two doubtful in- 

 stances, they do not give any support to the idea that barometric distur- 

 bances travel from the west across Afghanistan, and he therefore con- 

 cludes, that in most cases, if not in all, these disturbances originate in 

 India. Now it is only necessary to supply the omitted, but understood, 

 major premiss of this syllogism, viz., that barometric disturbances either 

 travel to us from the west across Afghanistan, or originate in India, — 

 in order to show that it cannot be accepted without positive proof, for 

 Quetta is surely not the only gate through which these disturbances 

 might enter India. The positive evidence in support of this premiss 

 will probably be forthcoming in Mr. Blanford's complete paper, but in 

 the mean time, I may point out that the minor premiss, viz. — that these 

 disturbances do not come to us from the west across Afghanistan — does 

 not appear to have a very firm foundation, and that the conclusion 

 cannot, therefore, be regarded as a satisfactory one. On looking over 

 the Quetta barometric curves, and comparing them with those of Bicka- 

 neer, I find the following instances of barometric minima which arrived 



