150 



SCIENCE. 



[Vol. VII., No. 158 



of tons of oil have been lost from an inability to 

 direct it into reservoirs, which are frequently not 

 even prepared before the need of them arises. 

 Some fountains are intermittent, and play from 

 one to two or three hours at a time, and then cease 

 for a day or so. These are the most convenient, 

 as they give plenty of time to arrange for collect- 

 ing the oil. In some cases the action has to be 

 started by withdrawing a few scoops of oil from 

 the bore, and thus disturbing the subterranean 

 equilibrium. 



Continuous fountains sooner or later become 

 intermittent, and then, like the latter, settle 

 down into ordinary wells, from w r hich the oil 

 must be raised by the usual methods. The jet 

 sent out of a bore-pipe appears urged forward by 

 a rapid succession of pulsations ; but periods of 

 quiet may be noted, during which the fountain 

 seems to gather up its strength for an extra ener- 

 getic effort. The height of the jet varies with the 

 intensity of the pulsations. A continuous fountain 

 may yield over thirty-three hundred tons of oil, 

 and require the labor of a hundred men to collect 

 and store it in reservoirs. The daily yield would 

 be worth five hundred dollars, the cost of labor 

 being from seventy-five to a hundred dollars. 



The condition of the oil is such, that, when no 

 longer forced out by internal agencies, it must be 

 removed from the bores by means of scoops : 

 hence the bore-holes have to be large, usually 

 sixteen inches in diameter, and, having to be 

 maintained at that diameter throughout, must be 

 lined with bore-pipes. The cost of these bore- 

 pipes is a serious item, in a well of six hundred 

 feet in depth costing twenty-five hundred dollars, 

 while the expense of sinking the bore amounts to 

 about five thousand dollars. 



The owners of allotments are free to sink their 

 bore-holes where they like : hence they are mostly 

 sunk along the boundaries of the plots, and not at 

 the points which the lay of the strata would indi- 

 cate to be the most advantageous. The reason for 

 this is, that each proprietor considers, that by 

 sinking a bore near his neighbor's plot, if he suc- 

 ceed, he will get his own oil and a good deal of his 

 neighbor's also. His neighbor is actuated by the 

 same motives : hence the allotments have the ap- 

 pearance of fortified places, being surrounded by 

 works, and unoccupied over the greater portion of 

 their inner areas. Naturally, if a bore be excep- 

 tionally successful, a large number of additional 

 ones are at once driven, and the yield of each is 

 in consequence reduced. 



The mean produce of the one hundred wells now 

 in action is given at thirty-two tons per well per 

 day, from March to November. The average cost of 

 production is about twelve dollars per ton, nearly 



five per cent of which is due to the scarcity of 

 water. 



' A commission appointed by the government 

 reports that a pipe-line from Baku to Batoum on 

 the Black Sea is indispensable for the higher 

 development of this industry, as at present not 

 one-half of the valuable products are obtainable. 

 The commission, however, thinks that the under- 

 taking should be left to private enterprise. The 

 Transcaucasian railway will in a measure aid in 

 the transportation. 



RATIO OF INCREASE OF HEIGHT TO IN- 

 CREASE OF BULK IN THE CHILD. 



Some remarkable observations, we learn from 

 the Lancet, have been recently made by the Rev. 

 Mailing Hansen, principal of the Danish institu- 

 tion for the deaf and dumb, on the progressive 

 increase in height and weight of children, one 

 hundred and thirty of whom were under his 

 charge. Of these, seventy-two were boys and 

 fifty-eight girls, and they were weighed in batches 

 of twenty, four times daily, — in the morning, 

 before dinner, after dinner, and at bed -time. 

 Each child was measured once a day. The 

 weighings and measurements extended over a 

 period of three years, and the results showed that 

 the increase in the bulk and height of the body 

 does not proceed at a uniform rate throughout 

 the year. Three distinct periods, with some 

 minor variations, were observed. In regard to 

 bulk, the maximum period extends from August 

 until December; the period of equipoise lasts from 

 December until about the middle of April ; and 

 then follows the minimum period until August. 

 In regard to height, the maximum period corre- 

 sponds to the minimum period of increase in 

 bulk. In September and October a child grows 

 only a fifth of what it did in June and July. So 

 it appears that during the autumn and the begin- 

 ning of winter the child accumulates bulk, but 

 the height is stationary. In the early summer, 

 on the other hand, the bulk remains nearly un- 

 changed, but the vital force and nourishment are 

 expended to the benefit of height. When the 

 body works for bulk, there is rest for growth, and 

 vice versa. Mr. Hansen has observed a similar 

 ratio of increase of bulk to increase of height in 

 trees. In regard to the minor variations observed, 

 it is probable that they are dependent, in part at 

 least, upon the external temperature; so that, 

 when tin's runs up, there is marked increase in 

 weight, while a diminution of weight occurs with 

 a fall of temperature. 



Mr. Hansen's observations arc undoubtedly of 

 considerable importance. Similar ones have been 



