ENGINEERING IN 1892. 



Tin- Columbia Kher Jetties. Since 1884 

 this uiviit work has been in progress. It has in 

 tie making of a channel over a dangerous 

 bar at i he mouth of the river, the contract call- 

 ini,' for a depth of 30 feet at low tide. This is to 

 "inplished in the usual way, by concen- 

 trating tin- current and increasing its power of 

 Burying away sand and other deposit. As the 

 work now stands, it is a low-tide jetty, extend- 

 ing westward from Fort Stephens with a slight 

 curve to the south, the length being about 4$ 

 miles. The ordinary mat tress- fascine construc- 

 tion was used, the foundation being about 40 feet 

 wide and from 2 to 5 feet thick ; this, of course, 

 i< below water at all times, and upon it is placed 

 tlie rockwork, extending to a level of 4 feet 

 above mean low water. The latest report of 

 ('apt. T. W. Symons, of the United States Engi- 

 neers, says that before the work was begun the 

 channels over the bar were variable in depth and 

 capricious in location ; sometimes there was but 

 one channel, and at other times there were three, 

 varying in depth from 19 to 21 feet. The re- 

 sults already attained are extremely satisfactory. 

 There is one straight-out-and-in channel a quar- 

 ter of a mile wide and nowhere less than 29 feet 

 deep. About 25,000 tons of rock have been used 

 in securing the jetty and protecting the build- 

 ings. The original estimate for the construction 

 was $3,000,710, and it is likely that the work can 

 be finished within those figures. 



Government Railways in Snmatra. 

 Dutch rule in Sumatra has so stimulated com- 

 mercial interest that a comprehensive railway 

 system has been undertaken, under the direction 

 of Mr. Post, a Dutch engineer. The engineer- 

 ing difficulties have been very great, owing to 

 the mountainous character of the island and the 

 steep gradients and sharp curves that everywhere 

 have to be overcome. In general terms, the line 

 extends across the most densely populated part 

 of the island, its high central plateau touching 

 the principal inland towns and reaching the coast 

 at Port Emma, the terminus. The line ascends to 

 an altitude of 3,785 feet above sea level, and 

 crosses a formidable volcanic range whose Su- 

 matrian name signifies " destroying fire." This 

 section presents gradients as steep as 1 in 12, 

 and these are overcome by means of mechanical 

 appliances on the engines, consisting of 2 coupled 

 axles combining adhesion wheels and cogged 

 wheels, which can be used at the engineer's 

 pleasure according to the steepness of the grade. 

 For connection with the cog wheel, a central, 

 laddrrlike rack is bolted to the ties between the 

 ordinary rails. Two types of ties are employed, 

 both being of iron, since wood decays so rapidly 

 in that climate as to be unavailable. The en- 

 gines are provided with 3 kinds of brakes 

 spring, air, and a tooth-wheel brake, which is 

 capable of arresting the mechanism. All the 

 machinery has to be of the simplest character 

 possible, because the only engineers available in 

 Sumatra are not accomplished mechanics, and 

 complicated machinery is entirely beyond them. 

 The locomotive is always coupled to the rear of 

 the train, pushing it on the up grades and hold- 

 ing it back during descents. The cars are of the 

 American type, and are arranged for two classes 

 of travelers. One feature, at least, in the con- 

 struction of this line was very interesting and 



: running water was utilized for the 

 purpose of carrying earth and depositing it at 

 the places where it was required. This was ef- 

 fected by means of small canals of steep gradi- 

 ent, sometimes several miles long. The labor- 

 ers stir up the earth and the water that car- 

 ries it down steep inclines to places where it is 

 desired to construct an embankment. Here bar- 

 riers of bamboo are set, which permit water and 

 soluble material to pass, while the solid earth, 

 gravel, and sand settle down and form an em- 

 bankment. So solid are these deposits that it is 

 perfectly safe to cross them on foot or on horse- 

 back while the water is still flowing over the 

 surface. The loss of material is sometimes as 

 high as 30 per cent., but the saving in time and 

 labor largely overbalances this. 



Artesian Well. An interesting but unsuc- 

 cessful attempt was made at Galveston, Texas, 

 to secure an ample supply of pure water. The 

 city at present draws its water supply from 13 

 wells ranging from 825 to 1,350 feet deep. It 

 was decided to expend $75,000 for a well at least 

 3,000 feet deep. The work was done in the usual 

 way, beginning with a section of 15-inch pipe, 

 telescoping smaller sections, and ending with 

 pipe of 9 inches in diameter. No water was 

 reached, but the result of the borings was of in- 

 terest. They were as follow : Gray sand, 46 feet ; 

 red clay and shells, 18 feet : blue clay and wood 

 fragments, 36 feet: sand and seashefls, 215 feet; 

 sand and clay, 600 feet ; sand, clay, and sea- 

 shells and wood, 688 feet; and the remainder, to 

 a depth of 3,070 feet, was sand, clay, and large 

 logs. At this point, the contract having been 

 more than fulfilled, the boring ended in a bed of 

 seashells. 



Flexible Water-Pipes. Engineers have re- 

 peatedly considered the practicability of laying 

 water mains in the beds of rivers for the pur- 

 pose of supplying fresh water to cities at the sea- 

 board ; but there have been many difficulties to 

 overcome, and it has not been undertaken on a 

 large scale. During the past summer a new plan 

 has been adopted by the authorities of Rotter- 

 dam for laying pipes in the bed of the River 

 Maas. A difficulty that had to be surmounted 

 was found in the very large and continuous traf- 

 fic of the river. Eventually a flexible tube was 

 constructed, consisting of short sections con- 

 nected with ball joints ; each pipe is 23 inches in 

 diameter, made of steel and provided with steel 

 flanges. The ball joints are of cast iron. In 

 sinking the pipes to position, 2 barges were fast- 

 ened together and an inclined platform about 

 120 feet long was hung freely between the two. 

 The pipe sections were built up on this platform, 

 and as each joint was completed the barges were 

 hauled astern so that the lowermost section slid 

 off and was deposited on the bottom of the river, 

 leaving room at the top of the incline for the at- 

 tachment of the next section. The depth of the 

 river averages 36 feet, and work progressed at 

 the rate of about 85 feet a day. The whole 

 length of the tube was about 3.000 feet. 



Submarine Borings in Northumberland 

 Straits. Work has actually begun on the tun- 

 nel connecting the mainland of New Brunswick 

 with Prince Edward Island, but it has not pro- 

 gressed far enough to justify description here. 

 The engineer who had charge of the preliminary 



