importance expected to flow from it. It is expected, for instance, that the tunnel will form the great highway or outlet for the ores of the Comstock, which are at present hoisted to the surface, and thence transported to the mills on the Corson River, a distance of some twenty miles. By the erection of mills at the mouth of the tunnel, the cost of transportation (which is now very considerable) could be greatly reduced. It will also render possible the profitable working of low-grade ores, of which enormous quantities remain in the mines untouched.

Work on the tunnel was commenced on October 19, 1869, and has been steadily continued until the present, when but little more is required to complete it. The total amount expended on the work thus far will foot up to about $3,000,000. Some $500,000 more will be required, on completion of the tunnel work, to provide it with a double track, and bring it into complete working order with the paraphernalia for wire-rope transmission, etc.

STEAM-MOTORS ON CITY RAILWAYS.

In addition to the satisfactory progress made during the past year towards the completion of the elevated-railway plant, designed to secure rapid transit in New York City, the substantial progress made in other cities in introducing steam-cars on the street-railways is worthy of special notice. This movement was inaugurated by the Market Street City Passenger Railway Company of Philadelphia, which in the month of March, 1877, put into operation seven steam-cars, with the avowed purpose of giving them a thorough and continuous practical test. The experiment appears up to the present time to have proved quite successful, as all the cars have continued in operation since they were put on without difficulty or objection. The cars are noiseless in operation, and the anticipated trouble from the escaping steam has proved to be groundless. The operation of these cars has shown, it is affirmed, a notable economy over the common plan of horse traction which they replace. The success of this experiment appears to have attracted attention to the question, and a considerable number of steamcars have been introduced during the past year upon the street-railways of other American cities.

The cars above alluded to are of the self-contained type, in which engine and car are combined. Apropos of this subject, which naturally provoked much discussion in the engineering journals, the Railroad Gazette, whose professional opinions are entitled to high consideration, intimates that the most rational solution of the steam street-car problem will be found in a light steam-engine, which may be coupled to and detached from the common street-cars as horses are. This plan has been tried in several cities (Baltimore, Philadelphia, New Haven, Dubuque, Havana, etc.) with good results. It would admit of the use of the present cars, which the self-contained steam-cars do not permit (and this fact, incidentally remarked, is one of the most serious obstacles in the way of introducing steam on the city railways, since the substitution of specially constructed steam-cars would render the present rolling stock, in which large capital is locked up, practically valueless). An accident to either the car or engine of one of these self-contained cars lays up the whole apparatus for repairs; while an accident with the independent system might lay up a car or an engine, but would leave one or the other free for use, as the car could be coupled to another engine, or the reverse.

The subject also appears to have attracted an unusual share of attention abroad, especially in England and France. In Paris, for example, not less than thirty-five steam-motors were in daily use about August last; and new lines coming to the very heart of the city were under construction, which were to be operated by steam. It appears probable, therefore, that during the past year we have witnessed the initial steps of an innovation destined shortly to replace very largely the old system of horse-power traffic in cities.

THE PATENT MODEL SYSTEM.

A question which vitally concerns the inventors of the country, and which has given rise to much discussion pro and con, is the proposition to abolish the system, so long in vogue, of demanding models of inventions to accompany the application of the would-be patentee. The recent destruction by fire of a portion of the Patent-office building, in which these models were stored, and the destruction of a large number of them, gave the opportunity for the oppo

nents of the existing system to begin a war against it. The main arguments of those who favor the abolition of the model-system are, substantially, that in the great majority of cases a model is unnecessary, since the invention can be quite clearly and understandingly shown by a properly finished drawing; that the rule making models obligatory, as the law now practically stands, is an unnecessary and burdensome tax upon the resources of the inventor class, the cost of models being often so great as to deter inventors from patenting their inventions; that, in view of these facts and others of minor importance, it is unjust to tax twentynine inventors with the expense of a model which experience has shown to be necessary only in the thirtieth case; and that the system should be so changed as to require inventors to present models only in cases where, from the nature of the subject, the ideas of the would-be patentee cannot be properly understood by drawings alone, or in cases of suits in interference, etc., where they may be reasonably supposed to be necessary and of service. The conservative element that favors the continuance of the status quo urges in substance, that, so far from being a hardship to the inventor class at large, it is really the best and only trustworthy safeguard against the wholesale pirating of patented inventions; and that, admitting that models may be in many cases dispensed with as unnecessary, and that in certain of such cases the rule requiring models may work individual hardship, the abandonment of the general rule would be unwise, and would operate disastrously upon the inventor class by bringing about a general depreciation of property-value in patents —a result which, it is strongly maintained, would be sure to follow the invitation to fraudulent practices which would. be afforded by the absence of models, and the consequently greatly multiplied difficulties the examiners must then have to contend with in deciding the question of originality.

It appears probable, at the time of this writing, that the discussion may result in a modification of the existing laws on the subject, by which the Commissioner of Patents will be vested with larger discretionary powers to demand models only where, in the judgment of examiners, they are deemed desirable or necessary.

SHIP-CANAL PROJECT ON THE SEINE.

The preliminary arrangements are being made at Havre, at the time of this writing, for the construction of a maritime canal from that port, touching at Harfleur, and joining the Seine at Tancarville, a point on the river about sixty miles below Rouen. This improvement is projected for the purpose of obviating the dangers of the navigation of the Lower Seine by reason of fogs, the shifting sands, and the violence of the tidal wave. According to description, the canal will consist of a single section of about seventeen miles in length, the western outlet of which will be in the Eure Dock at Havre. The plans adopted contemplate a canal with a minimum breadth of twenty-five meters. Plans have also been elaborated for the deepening of the channel of the Seine between Paris and Rouen to 3.20 meters; and the canal between Havre and Harfleur is designed to have a depth of 4.5 meters, to accommodate the passage of vessels of considerable draught of water. The work is estimated to cost about 21,000,000 francs, which will include all accessory works, the planting of the banks with trees, the construction of a branch five hundred meters long to connect the port of Harfleur with the canal, and a basin of five hundred by sixty meters at Havre. We make the above statements on the authority of Saward's.

THE ALGERIAN INLAND SEA.

Last

This project, which received notice in our last year's Record, appears to be further from realization than ever. year it appears to have been the subject of considerable discussion in French scientific circles, and to have aroused some very serious objections to its advisability. The objectors are MM. Naudin, Dumas, and Daubrée, and their objections are based upon sanitary grounds. Their arguments as quoted in the London Engineer are as follows: To fill with saltwater the shallow basins of the region which it is proposed to convert into an inland sea would be equivalent to reproducing in Algeria all the evil features of a series of marshes. The deepest portion would, it is admitted, not exceed eighty feet in depth, and the whole coast-line would be so shallow as to be but little else than a marshy bank, which, under

the influence of a tropical sun for eight months of the year, would doubtless become a focus which would develop and distribute all the evils of malaria. M. Roudaire, the originator and champion of the scheme, has made a personal examination of the region between Biskra and the Gulf of Gabes, and estimates that his project will necessitate the removal of some 20,000,000 cubic meters of sand, the probable expense of which will be about 30,000,000 francs. The alleged advantages of this project we have detailed in previous volumes.

FLOODING OF THE SAHARA.

Mr. Donald Mackenzie has not yet abandoned his pet scheme for opening Africa to commerce by turning the waters of the Atlantic into the African desert. His present plan, as expressed before the Chamber of Commerce and the Philosophical Society at Bradford, England, is to utilize the vast plain or basin known as El-Jaf, containing an area of 80,000 square miles. This vast depression, which is affirmed by Mr. Mackenzie to be some two hundred feet below the ocean-level, and to have been formerly connected with the Atlantic Ocean by a channel now blocked up with sand, it is proposed to restore to its ancient condition as an arm of the sea by removing this barrier, and thus open a navigable highway for the commerce of the world to the very heart of Africa.

ANOTHER AFRICAN PROJECT.

The latest engineering scheme affecting this continent originates with Sir Samuel Baker, who proposes a plan by which not only the water of the Nile, but the silt (of which the greater portion is now wastefully deposited in the Mediterranean Sea), shall be turned to good account as a fertilizer of the deserts of Nubia, Libya, and the Soudan. He proposes in the London Times the construction of a system of engineering works by which a portion of the Nile floodwater, with its annual burden of soil robbed from the fertile slopes of the Abyssinian plateaux, shall be diverted into these deserts, where it may deposit its rich sediment on the sands, and also irrigate them, so as to transform a desert into "cotton-fields that would render England independent of America." This desideratum he proposes to accomplish