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RESEARCHES AND EXPERIMENTS. 



that any Bishop officiating without the sanc- 

 tion of the Bishop of the diocese was an intru- 

 der, and in the commission of an act of schism, 

 and that no blessing could follow the accepting 

 of the ministrations of such an intruder. Bish- 

 op Gregg replied from the pulpit, affirming the 

 validity of his orders and defending his con- 

 duct. 'During June Bishop Gregg held an or- 

 dination at Southend, when seven candidates 

 were admitted to deacon's orders, and some 

 presbyters were ordained, who it was under- 

 stood would labor at watering-places. The 

 first anniversary meeting of the ministers and 

 members of this Church in England was held 

 in London, July 5th. A sermon was preached 

 by Bishop Gregg. 



RESEARCHES AND EXPERIMENTS. 

 Mouchofs Solar Boiler. The results of experi- 

 ments made by Mouchot in Algeria, to deter- 

 mine the amount of heat obtainable in that 

 climate by the use of his "solar boiler," are 

 interesting. He employs reflectors either of 

 solid silver plate, or else of brass with a slight 

 coating of silver deposited in the electric bath. 

 The variations of intensity in the sun's heat 

 during the course of a day were studied, and 

 the result showed that, as a rule, with an un- 

 clouded sky, these variations were inconsid- 

 erable between 8 A. M. and 4 P. M. Next an 

 effort was made to ascertain the amount of 

 utilizable solar heat, to be obtained first at a 

 given place and at different seasons of the year, 

 and then throughout the whole of Algeria. In 

 this investigation he employed a solar boiler 

 whose rendement (that is, the quantity of heat 

 collected by it per minute per square metre of 

 surface) was, at Algiers, 7 calories in April, 8 

 in May, 8*5 in June and July. These figures 

 are exceeded in some localities. For instance, 

 on the Chellia Peak, altitude 2.328 metres, at 

 11 A. M. of August 19th, the apparatus gave 9 '7 

 calories ; at Oued Mzy, at noon of September 

 26th, it gave 9 '8 calories. M. Mouchot remarks 

 upon the significance of these figures. A ren- 

 dement of 7 calories, he observes, shows that a 

 reflector of one square metre surface would 

 boil a litre of water in less than twelve minutes, 

 and would in one hour produce 1,322 litres of 

 steam at normal pressure. 



Ventilation of Sewers. It is a fact well 

 known to sanitary engineers that if the air 

 contained in sewers could be kept continually 

 moving in one direction, so that stagnation 

 could not take place, the dangers attending the 

 development of sewer-gases would be avoided. 

 Vertical shafts have been tried for the pur- 

 pose of causing the sewer-gas to ascend, but 

 without avail. Similar shafts are again pro- 

 posed by a London engineer, R. Parker ; but 

 lie, instead of using them as uptakes, furnishes 

 them with cowls whose openings are always 

 presented to the wind. Through these open- 

 ings the wind enters the sewers and keeps up 

 a current, which constantly changes their gas- 

 eous contents by driving them out. Mr. Par- 

 ker s plan contemplates the use of a number of 



cast-iron shafts erected about 12 feet high and 

 10 inches in diameter, in convenient and open 

 places, and also pipes of various sizes according 

 to circumstances, from the sewers and drains 

 at the rear of houses to the housetop, as high 

 as the chimney-stack ; these pipes or ventilat- 

 ing shafts being surmounted by cowls, guided 

 by vanes, so that their opening shall always 

 face the wind. The air or wind will force 

 down the air within, and pass into the sewer 

 and travel along it, entering all drains, and 

 ramifying to find an outlet. Experiments made 

 "to see if the force of the wind and air could 

 be conducted into the sewers, in this way to 

 force out the gases and keep up a constant cur- 

 rent of fresh air," have shown that there is 

 always a downward current in the ventilating 

 shaft and an upward rush of pure air in all the 

 gullies and drains in its immediate neighbor- 

 hood. A shaft was constructed from a drain 

 to the roof of a house, the distance from the 

 cowl to the sewer being 13 feet. The average 

 results of seven experiments were : Tempera- 

 ture outside sewer, 43 '28 F. ; inside sewer, 

 48-86. Velocity of wind outside, 4'61 miles 

 per hour ; at junction of 9 inches drain in sewer, 

 1*81 mile per hour. Cubic feet of air forced 

 into sewer per hour, 4,210. 



The Danube and the Aach. It not unfre- 

 quently happens, in years of great drought, 

 that the water of the Danube, near its source, 

 almost entirely disappears in the fissures and 

 holes in the river's bed. The proprietors of 

 manufacturing works farther down stream have 

 frequently blocked these openings, to prevent 

 losses of water. But other manufacturers, 

 owning works on the Aach, a tributary of Lake 

 Constance, at the distance of a few miles from 

 the Danube, and at an elevation 500 or 600 

 feet less, contended that these holes and fissures 

 in the bed of the Danube open into water-pas- 

 sages connecting with the source of the Aach ; 

 hence they applied to the courts for an injunc- 

 tion to prevent the stopping of these outlets. 

 To test the correctness of this theory, 10,000 

 kilogrammes of common salt was thrown into 

 the Danube at the point where its volume 

 is most sensibly diminished. This salt reap- 

 peared in the water at the source of the Aach. 

 Another experiment was made, consisting in 

 mixing fluoresceine with the Danube water at 

 the same point. On October 9th, at 5 P. M., 

 about 50 litres of the fluoresceine was poured 

 into one of the openings in the river-bed. On 

 the morning of October 12th the observers 

 stationed at the source of the Aach perceived 

 the coloration of the water, which was of an 

 intense green, and grew deeper and deeper in 

 tone till the evening of the same day ; about . 

 3 p. M. of the 13th the green color had entirely 

 disappeared. 



Utilization of Blast-furnace Slag. A few 

 years ago the annual product of blast-furnace 

 slag in the Cleveland district (England) alone 

 amounted to between three and four million 

 tons, and this waste material was accumulating 



