TEE AGRICULTURAL JOURNAL. 



319 



Plant Moisture, 



IN his agricultural column of the 

 Manchesler Times Mr. James Long 

 writes : — 



Eeference has been made to the value 

 of mulch in order that loss of moisture 

 may be prevented, and that plants may be 

 abundantly supplied with all that they re- 

 quire. How much, then, do plants re- 

 quire ? Mr. Maxwell has taken the 

 trouble to ascei'tain by one set of experi- 

 ments how much moisture transpired 

 through the medium of three pieces of 

 sugar-cane. Two tubs were selected, each 

 with perforated bottoms; over each bot- 

 tom a piece of cloth was laid, and this 

 was followed by 1251b. of a selected soil, 

 the cloth being employed to prevent any 

 loss of the soil through the perforations. 

 The two tubs were placed in galvanised 

 iron pans of water, whicli was regularly 

 maintained at a given level. Tlie pans 

 were covered with glazed cloth, which was 

 moisture-proof, for the purpose of pre- 

 venting evaporation from the surface of 

 the water, so that all water lost by 

 evaporation would have to take place 

 through the surface of the soil, and by 

 -transpiration from the plant. In one of 

 the tubs three pieces of the seed cane were 

 planted, while the other was left just as 

 it was, and maintained as a check! The 



two tubs were placed in a position with a 

 southern exposure in the face of a strong 

 wind, but they were covered by a veran- 

 dah to prevent the acquisition of water by 

 rain. The two tubs were nuiintained in 

 this way for 7^ months, and it was then 

 found that the water which had evapora- 

 ted from the tub in which no plants had 

 been placed reached 83,140 grams, 

 whereas the water evaporated from the 

 other tub through the medium of both 

 soil and plants was 167,350 grams. Thus 

 it was shown that the water transpired by 

 the cine was 84,110 grams. The total 

 aiiiuuiit of dry matter produced by the 

 plant during the period of growth was 

 5G8.9 grams; for each gram of w^ater-free 

 cane material produced 147.8 grams of 

 water were transpired. Mr. Maxwell 

 points out that the application of the 

 same volume of water at the time of 

 planting and during the early period of 

 growth, when transiiiration is very low, as 

 is re(iuir('d by a plant later in "develop- 

 ment is fnlldw,.,] by a great loss of water 

 and of the soil constituents which the 

 water removes. These facts bear in- 

 directly, and directly too, upon water 

 meadows and general irrigation, and the 

 experiment furnishes many hints which 

 may prove serviceable to both instructors 

 and investigators in this country. 



The Udder. 



pROFESSOR H. HAYWARD says :- 

 i Doubtless you all know that the pro- 

 ductivity of an udder is dependent upon 

 the number of epithelial or secretive cells 

 it contains, and not necessarily iijjon 

 lis size. The ideal udder then 

 vvould be one of such a shape 

 that the maximum-sized udder con- 

 taining the maximum number of secret- 

 ing pells could be easily carried when full. 

 A little thought will show us that the 

 shape of the udder must necessarily form 

 part of an arc of a circle, but that both 



the back and front part of the udder will 

 extend beyond the circle, and thus form 

 what we know as a square, well-balanced 

 udder. The udder should, of course, be 

 free from much flesh. The amount of 

 flesh an udder will show on milking out, 

 hpweyer, will depend on the period of 

 lactation, as the more active the secretive 

 cells are, the more ai>parent flesh will the 

 udder show after milking. A fleshy 

 udder is readily distinguished by the fact 

 that superfluous flesh that it contains usu- 

 ally seems to drop more or less to the bot- 



