April 20, 1888.] 



SCIENCE. 



at which they are burned. From another long series of experi- 

 ments he finds the life of the lamps corresponding to the different 

 efficiencies. With these results, and assuming different prices of 

 current and lamps, Mr. Howell plots curves representing the total 

 cost of operating one hundred sixteen-candle power lamps for one 

 thousand hours ; the points of the curves being obtained by vary- 

 ing the efficiency at which the lamps are run, and calculating the 

 total cost from the data he has obtained and assumed. These 

 curves give a definite minimum corresponding to some definite 

 efficiency, the latter varying with the price of current and lamps. 

 These curves are important, as they enable us at once, knowing how 

 much the current costs, to select lamps that will give the best re- 

 sults. On comparing the cost of lamps with the total cost, Mr. 

 Howell finds that in every case the total cost is a minimum when 

 the cost of lamps is about fifteen per cent of the total cost, — a curi- 

 ous and important result. 



Electric Lighting and Insurance. — A reduction in insur- 

 ance rates, where electric lights are e.\'clusively used, has just been 

 voted by the New England Insurance Exchange. The reduction 

 is, however, only allowed where the rules of the exchange are fol- 

 lowed in installing the plant, and where the company whose ap- 

 paratus is used shall pay " any sum assessed as its proportion to de- 

 fray the cost of inspection." This move has several things to 

 recommend it : it gives to electric lighting the advantage which its 

 superior safety warrants, and it insures the careful installing and 

 regular inspection of the plant. It is in this last that the benefit is 

 greatest. The few fires for which electric lighting is responsible 

 have been the result of cheap and careless work, and with efficient 

 inspection this is impossible. With the wires and appliances that 

 can be purchased to-day, electric lights can be put in buildings in 

 away to make accident impossible, and electricians can thank their 

 own ill-advised ' economy ' for the ill repute in which some people 

 hold the system. 



The De Bernado Accumulator. — It is possible that in the 

 final perfected type of accumulator, different patterns will be used 

 for different purposes. At present the ' grid ' type of battery-plate 

 used for lighting-purposes is much thicker and heavier than that 

 used for traction-work. It has long been acknowledged, that, 

 where a very heavy current is to be taken from a cell, the Plante 

 form of plate is preferable to the former, in which the active mate- 

 rial is pasted into perforations in cast-lead plates ; and there seems 

 a tendency, especially in France, to return to some modification of 

 Plant6's original idea. De Bernado requires in his welding process 

 a heavy current of electricity ; and to obtain it he has devised a 

 new form of accumulator, which will stand the discharge rate re- 

 quired without any very rapid deterioration. The cell does not 

 differ greatly from the Kabath accumulator, which attracted atten- 

 tion some years ago, but which is now little used. The plate con- 

 sists of a frame of lead, with lead strips passing from one side to 

 the other of the framework. The alternate strips are corrugated 

 obliquely to give circulation, and all of them are burned at their 

 ends to the frame. The plates so made are ' formed ' by the Plante 

 process; that is, by reversing the direction of the current passing 

 between two sets of plates immersed in sulphuric acid, at intervals, 

 until an ' active ' coating of sufficient depth is produced. There is 

 nothing especially new about this battery, — it differs but little 

 from the Kabath accumulator, — but it is of interest as indicating 

 the gradual return to the original Plante form, or some modification 

 of it, that is gradually taking place, especially where rough usage 

 is necessary. 



HEALTH MATTERS. 

 Lung-Expansion and Consumption. 



Dr. Thomas J. Mays of Philadelphia, in a paper read before 

 the Philadelphia County Medical Society, still further elaborates the 

 theory which he has repeatedly expressed, and to which Science has 

 before referred. This theory is, that an insufficient expansion of 

 the lungs, especially of their apices, has more to do with the devel- 

 opment of consumption than the breathing of impure air, and that, 

 for the prevention of the disease, complete expansion of these or- 

 gans is more important than the breathing of pure air. The title 



of his paper is ' Apex-Expansion versus Pure Air in Pulmonary 

 Consumption.' 



Although Dr. Mays acknowledges that wholesome air is of value 

 in the prevention and treatment of consumption, still he is convinced 

 that the purity of the atmosphere plays but a small part in the re- 

 sult. He cites the almost complete exemption from pulmonary 

 consumption of the inhabitants of Iceland, Greenland, and Lapland, 

 whose habitations are notoriously wanting in ventilation, as proof 

 that this disease is not the result of breathing a vitiated and impure 

 atmosphere. On the other hand, people living in tropical regions, 

 who are out of doors most of the time, are by no means free from 

 consumption. Miners and laborers in coal-mines, although con- 

 tinually respiring an atmosphere loaded with impurities, and damp 

 and musty, suffer but very little from this disease. 



That which has been an important factor in establishing the be- 

 lief that pure air is such an essential element in limiting the ravages 

 of consumption, is that those who occupy elevated or mountainous 

 regions are less liable to this disease than those who live near the 

 sea-level. In reference to this fact. Dr. Mays says that it is esti- 

 mated that at an elevation of six thousand feet the surface of the 

 body is relieved of nearly seven thousand pounds' pressure. When 

 such an enormous weight is lifted from the body, it is quite evident 

 that its interior must also be markedly affected : the pulse is accel- 

 erated from fifteen to twenty beats per minute ; the respiration is 

 quickened from ten to fifteen breaths per minute ; and evapora- 

 tion from the skin and lungs is increased. These are some of the 

 immediate effects. Protracted residence in such a high region en- 

 larges the chest capacity. The Quichua Indians, who dwell on the 

 elevated tablelands of Peru, have enormous-sized chests, containing 

 capacious lungs with large air-cells. The Mexican Indians possess 

 chests which are out of proportion to the sizes of the individuals. 

 Dr. Denison says that children born in the Rocky Mountains have 

 chests of unusually large capacity, and M. Jaccoud states that at 

 St. Moritz the respirations are not only more frequent, but fuller. 



The reason why the number of respirations increases while as- 

 cending a high elevation becomes clear when we take into consid- 

 eration the fact that at the sea-level a cubic foot of dry air contains 

 about 130 grains of oxygen, while at an elevation of six thousand 

 feet it contains only about io6 grains, — nearly twenty-five percent 

 less than the body is accustomed to breathe at or near the seaboard. 



Professor Mosso has recently proven experimentally that man 

 possesses a lung capacity which is nearly one-fourth larger than the 

 actual necessities of life at the sea-level demand ; hence by employ- 

 ing his whole lung capacity he can extract a sufficient amount of 

 o.xygen from this attenuated atmosphere without difficulty. And 

 herein lies the secret why so many consumptives, and others with 

 weak lungs, derive such a great benefit when they resort to a 

 mountain climate. Every available space in the chest is brought 

 into requishion to furnish the needed amount of oxygen, the apices 

 are called out of their lethargic state, and the alveoli are inflated ; 

 and, if the infiltrated areas are not dispersed, the surrounding 

 alveoli are kept permeable, and so the disease is at least limited, 

 and called into abeyance. 



In concluding his paper, Dr. Mays says, " Now, after reviewing 

 the whole subject, we are driven to the conclusion that the line of 

 immunity from consumption, which in the early history of our 

 country was located at the Atlantic seaboard, and which has 

 gradually receded westward with the tide of civilization, until at 

 present it has reached the latitude of Colorado, will not stop in its 

 course until it touches the shores of the Pacific ; that the question 

 of curing the disease does not depend on the purity or freshness of 

 the air, or upon the number of bacilli which the atmosphere may 

 contain, or upon the amount of oxygen which may be introduced 

 into'the body, for these are all secondary considerations ; but it is 

 simply a mechanical question, — a question as to the best mode of 

 expanding the lungs, and especially the apices of our round-shoul- 

 dered and flat-chested patients, of removing the infiltrated products 

 already existing, and of enhancing the constitutional resistance." 



Leprosy in America. — The recent cases of leprosy in Phila- 

 delphia have been the means of awakening a new interest in that 

 loathsome disease. Dr. Charles W. Allen, in the New York 

 Medical Journal, gives a most complete account of the disease, 

 and the views of the best authorities regarding its communicability. 



