( 91 ) 



The seasons should be clearly defined, and the rainy and dry seasons (If marked) should 

 always be taken as the principal divisions of the year. In some countries (not Indian) 

 two dry and two wet seasons succeed each other alternately. The hygrometrical observations 

 may be reduced to the degree of humidity (saturation = 1 or 100,) and entered as such in 

 the column allotted for this purpose in form 2 ; but the difference between the dry and wet bulb 

 thermometer alone would sufficiently answer the purpose. The remarks on dew, etc. can 

 only be very general. Daily means of temperature and humidity are in my opinion in- 

 sufScient for practical questions, and, therefore, the three periods of the day (applicable chiefly 

 to the plains and lower hills of India) should be kept separate, as is done in form 2. 



If it were possible to establish a series of observing stations in a net- work all over India, 

 even for a period of three or four years, and if the observations were made upon a uniform 

 plan, results could be obtained equally important to the forester and to the agriculturist. 



The reduction of the meteorological results of the various stations to climatological zones 

 or districts, is a very difficult task, if done properly, and it can only be carried out with a 

 perfect knowledge of the physical and geological conditions of the province itself. It cannot be 

 based upon the annual means, but must be deduced from the montlily means with due con- 

 sideration of the extremes and seasons. Besides this the stations themselves would have to 

 be classed first according to elevation and exposure, and, of course, the lower stations with free 

 exposures would have to form the basis. 



The subjoined schematic section of a range, about 3000 ft. high, supposed (for the sake of 

 simplicity) to run from N. to S., thus giving E. and W. exposures, may explain the points at 

 issue; 



Zt^IjOZt/AP' StcLtLOfV. 



(/"Upper Station,. 



Here L.^"* will shew a tolerably similar climate, but L.^* is sheltered in afternoon by the 

 range and thus escapes the maximum-temperature which usually falls in excessive climates 

 between 3 and 4 p. m. IJi"^ will also resemble one another, but U* may have a lower 

 temperature, while TJ" and U"" may have a climate similar to U^. U", although hypsome- 

 trically a lower station, will possibly shew a still lower temperature on account of its situation 

 in a deep sheltered valley. If the same range was composed of impermeable instead of 

 permeable strata, as here supposed, the result of both, if compared inter se, would differ 

 greatly. 



; 2. Soil. 



This factor has been already sufficiently treated of in the first part of this report and it 

 remains for me only to add some general remarks connected with it. 



1. Chemical composition of soiL A forester can possibly do little in this direction,* 

 beyond consulting a professional chemical man in all cases where he suspects that 

 the chemical composition has produced a certain change in the vegetation. Cliemical analysis 

 indicates but incompletely the fertility of soil, for it gives only the proportion, but not the de- 

 gree of solubility of the compounds. We must, moreover, dismiss the idea that any species 

 13 absolutely restricted to a substratum of a certain chemical quality, but still it would be 

 wrong to neglect this question altogether. Neglect of the chemical character of the substra- 

 tum is only too often the cause of failure in tree plantations in India which is caused either 

 directly, by planting trees where the substratum is diametrically opposed to their requirements 



* However, he should be generally acquainted with the principles of chemistry and be able to detect 

 himself the more prevalent and important compositions, such as limestone, silica, etc. German Forest-literature 

 comprises books on Chemistry adapted to Forestry : but I am not acquainted with a simihir English one. For 

 elementary instruction the following may be useful to tlie Forester ; Henry Roscoe, Lessons in Elementary 

 Chemistry. Liebig, Familiar letters ou Chemistry and Johastou, Injitructious for the analysis of boile. 



