Volume 08 (1864) (474 pages)

168 Ghe Mining and Scientific Lress. aiining and Scientific Press. A LOE CONN BS a nso andi ooooAapa ioe pennottaco RASA Seyior Epiror. c. W. of. SMITH, W. 5, EWER, A, T. DUWEY. DEWEY & CoO., Publishers. Orrick in the Government Honse building, Northwest corner of Washington and Sansome strects, rooms No. 56 and 57, up stairs. Terms of Snbseription: One copy, per annum, in advance,. One copy, six inoulhs in advance,. bgp For sale by Carricrs and Newsdcalers.~GY $5 10 300 Terms in Advance,—Having adopted the cash system, atu pay ments for subscriptions must be nade in advance. If old subscribers find their paper discontinucd at any timc, don't slop to grumble about it, but sendin the eash for anothcr year. ‘Equality is Fustice,” and we shall adininistcr this doctrinc:to all our patrons, as well as “the rest of mankind.” For Sending East, no more valuable or appropriate publication can be selected than the Mining ann Screntiric Press. For sale by the principal newsagents. AMERICAN AND Forricx PaTENTS.—Letters Palent for Inventors can be secured in the Uniled Stales and foreign countries through the Minsine ann Sciuentiric Press PATENT AcEncy. SVYe offer applicants reasonable térms, and they can rest assured of a strietcompliance with our obligations, and a fallhful perforimanco of all contracts. For reference, we will furnish lhe names of numerous partics for whom we have obtalned palents during the past year. Favoras.e to Inventors.—Persons holding new inventions of machincry and imporlant improvemcnls, can have the same illustrated and explained In the Minine anp Scientiric Press, free of charge, if in our judginent Ihe discovery is one of real merit, and of sufficient interest to our readers to warrant publication. WVIll be Discontinued.—After this date subscriptions not paid for in advance will be diseontinnued. As soon as possible bills wilt be prescnicd for all arrearages. Parties who rcecive a paper from the office of delivery cannot evade the Law requiring payment for the saine. We shallin fulure keep no continned accounts with subacribers, aud the subscriptions of aut fricnds and patrons will be treated aliko. San Francisco: Saturday Morning, March 12, 1864, EARTHQUAKES. Earthquakes are a complex phenomenon, referable toa diversity of causes. ‘Their occurreuce in a given region may no doubt be attributed to a special, local cause, entirely differing from the cause which may produce similar effects in another region. Again, various causes may act conjointly, or uuder various mutual modificatious. The phenomena of earthquakes have been made a matter of much investigation, and long contiuued and close observation. Great numbers of facts have been carefully noted, and well established. No single theory has yet beeu proposed which will account for all, or even the half of the facts established. When subjected to rigid investigation, all the theories yet enunciated are found to fail, at times; generally in a majority of cases, always in a large proportion. Some idea may be formed of the amount of attention which has been devoted to this class of investigation from the fact. that one important theory has been based upon the observation of more thau six zhousand days of earthquakes ! Modern appliances and facilitics are opeuing great opportunities for observatiou in this direction as, indeed, in almost every other department of scientific research. Jor instance, the Government Coast Survey has had, and probably now has self-registering tide gauges at this port (San Francisco.) San Diego and at the mouth of the Columbia river, which re. cord the rise and fall and time of tide at those several points upon a continuous sheet of paper, moved forward regularly by clock work. It was by this instrumeut that we were enabled, to announce upon this coast, the probable occurrence, in a distant quarter, of a great earthquake, weeks, if not months before it was made known, by due course of mail. It will berecollected by most of our readers that in December, 1854, Siinoda, in Japan, was visited by a terrible eartbquake, which completely emptied that harbor of its water, and left eveu ships of war upon dry land, which but a moment before had been proudly ridiug at anchor. Of course such a disturbance created an immense wave, which swept over the greater part of the Pacific ocean. It was felt in this harbor in just twelve hours and sixteeu minutes from the time the shock spent its force in the harbor of Simoda. The clock work register, above alluded to, promptly and faithfully recorded its appearance, and told our citizens, oue bright calm day, that a series of earthquake waves had visited us, recording their maximum hight as seven-tenths of a foot. That wave had traveled 4,800 miles and oeceupied half an hour in rising and falling. It was followed by several smaller ones, in quick succession. A similar record was made at San Diego. The great earthquake at Lisbou sent a wave quite across the Atlautic ocean. It was felt along the coast line of America from South Carolina on the south, to about the middle of the Labrador coast, on the north. The gradually increasing exteut of telegraphic communieation, is greatly facilitating observations with regard to the time, extent and veloeity of these wares, all of which data are of mnch importance in investigating the producing causes of these wouderful phenomena of nature. Earthquake waves are not confined to the water. They are also developed upon land, and what may appear somowhat strange to the uninitiated, they move far more rapidly through that element thau through water. An earthquake wave travels through water at the rate of about seven miles a minute; through earth at the rate of from fifteeu to fifty oreighty. Its rate in water is nearly uniform ftom the fact that that element is quite homogeneous ; while in passing through land or earth the advancing wave is oftentimes retarded by having to traverse various descriptions and strata of ground, often eucountering caverns, fisures and seams which greatly retard its velocity. Ihe more dense and homoge. neous the body the more uniform the transmission of the wave. Numerous and well attested observations prove beyond a doubt, that the undulating motion felt during‘an earthquake is a@*‘wave,” and quite simi'ar in character to an ocean waye. We will instance several observations which are well autheuticated, and which have been employed, in the way of illustration by Sir John Hershel. We quote :— “The way, then, that we may conceive an earthquake to travel, is this:—I shall take the case which is most common, when the motion of the ground to aud fro is horizontal. J/ow far each particular spot on the surface of the ground is actually pushed from its place there is no way of ascertaining, since all the surrounding objects receive the sanie inypulse almost at the same instant of time, but there are many iadicutions that it is often several yards. In the earthquake of Cutch, trees were seen to flog the ground with their branches, which proves that thet stens niust have been jerked suddenly away for some considerable distance and snddeuly pushed back; and the same conclusiou follows from the sudden rise of the water of lakes on the side where the shock reaches them, and its fallonthe opposite side; the bed of the lake has been jerked away for a certain distance from under the water and pulled back. Now suppose a row of sixty persons, standiug a mile apart from each otber, in a straight line, in the direction in which the shock travels, at a rate we will suppose, of sixty miles per minute, aud let the gronnd below the first get a sudden and violent shove, carrying it a yard iu the direction of thenext. Since this shock will not reach the next tillafter the lapse of one second . of time, it is clear that the space between the two willbe shortened by a yard, aud the grouud—that is to say, not the mere loose soil on the surface. but the whele mass of solid rock below down to an unknown depth—compressed, or driven into a smaller space. It is this compression that carries the shock forward. The elastic force of the rocky matter, like a coiled spring, acts both ways; it drives back the first man to his old place, and shoves the second a yard nearer to the third, and soon. Instead of men place a row of small buildings, or columns, and they will tumble down in succession, the base flying forwards, and leaving the tops behind to drop on the soil on the side from which tbe shock came. ‘This is just what was seen to happen in Messina in the great Calubrian earthqnake. As the shock ran along, the houses on the Faro were seen to topple down in succession, beginning at one end and running on to the other, as if a succession of mines had been sprung. In the earth-. quake of Cutch, a sentinel standing at oue end ofa long straight line of wall, saw the wall bow forward . and recover itself, nat all at ones, but with a swell like a wave running all along it with rapidity. In this case it is evident that the earthquake wave must ae had its front oblique to the direction of the wall.” ‘The earthquakes to which we have more particularly alluded were donbtless produced by deep seated disturbances, most likely originating in the high temperature of the far interior of the earth. We so judge mainly from their great severity and wide spread effects, the shocks traversing through and beneath extensive mountain ranges and across wide oceans. <A large majority of the earthquakes recorded are of a milder type, some of which may doubtless be attributed to the same causes as above noted, but variously and more geutly developed ; while many, most likely, have their scat of disturbauce nearer the surface, and are caused by sudden chemical changes, occurring within the solid crust of the globe, without any counectiou with internal fires. This leads ug to speak more particularly, but briefly, of ; CALIFORNIA EARTHQUAKES. There are many reasons for believing that the earthquakes which are of such frequent oecurrence throughout the valleys aud Coast Rauge of Califor~ niaare produced by the minor ageucies alluded to. A notieeable faet conuected with California earthquakes is, that those felt on the coast and in the valleys seldom if ever extend to the Sierra Nevada Range. Among all the shocks which have been experienced in San Francisco since the advent of the gold seekers, we have no recollection that any one of them has been seriously felt beyond the lower foot hills; and vice versa. ‘The earthquake which was so sensibly and extensively felt throughout the Sierra Nevada, and npon both its flanks, in the summer of 1860 (we believe we are correct in the date) was but barely perceived, if at all, in Sacramento, and not at all west of that city. These circuinstances go far towards establishing the theory, we have suggested, with regard to the seat of earthquake disturbances in the valley portions of the State, and to disprove the idea that they are consequeut upon the internal fires which are supposed to have a permanent existence bnt a few miles below the earth’s surface. We do not recollect havicg seen any recorded observations, or speculations even, upon the fact, but we have beeu led to eonclude, from the geueral directions which California earthquake waves appear to take, (from N. W. to 8. HE.) and from the limited spread of the wayes in au east and west direction, that the strata connected with tho Sierra Nevada range of mountains entirely underlies, not ouly the Sacramento and San Joaquin valleys, but probably the Coast Rauge also. If such be the fact it would follow as a matter of course, that any disturbance of the strata above this underlie would have very little teudency to effect the Sierra Nevada mountains. It is a welf known fact that a certain class of earthquakes throw out their waves, in concentric circles, without any reference to the direction of opposing nountain chains, passing freely across and through them, while others move longitudinally along extensive valleys, or along the directiou of mountain ranges. ‘I'he seat of disturbance in the latter c’ass is evidently near the surface, and it is to that class that our California earthquakes undoubtedly belong. We apprehend there can be very little doubt but that the dip of the Sierra Nevada completely underlies the scat of earthquake disturbance in the Sacramento valley and Coast Range region; hence we have but little reason to fear any very serious disturbance, such as would endanger the stability of buildings, ete., which have been crected with due regard for ordinary contingences. If this hypothesis can be sustained it willafford a vast amount of relief to the more sensitive portion of our population, both in the city and at the mines. Notwithstanding the appreliensions that have been felt. in many quarters that we may yet be visited with a destructive earthquake, we believe there is

168 Ghe Mining and Scientific Lress. aiining and Scientific Press. A LOE CONN BS a nso andi ooooAapa ioe pennottaco RASA Seyior Epiror. c. W. of. SMITH, W. 5, EWER, A, T. DUWEY. DEWEY & CoO., Publishers. Orrick in the Government Honse building, Northwest corner of Washington and Sansome strects, rooms No. 56 and 57, up stairs. Terms of Snbseription: One copy, per annum, in advance,.. One copy, six inoulhs in advance,.. bgp For sale by Carricrs and Newsdcalers.~GY $5 10 300 Terms in Advance,—Having adopted the cash system, atu pay ments for subscriptions must be nade in advance. If old subscribers find their paper discontinucd at any timc, don't slop to grumble about it, but sendin the eash for anothcr year. ‘Equality is Fustice,” and we shall adininistcr this doctrinc:to all our patrons, as well as “the rest of mankind.” For Sending East, no more valuable or appropriate publication can be selected than the Mining ann Screntiric Press. For sale by the principal newsagents. AMERICAN AND Forricx PaTENTS.—Letters Palent for Inventors can be secured in the Uniled Stales and foreign countries through the Minsine ann Sciuentiric Press PATENT AcEncy. SVYe offer applicants reasonable térms, and they can rest assured of a strietcompliance with our obligations, and a fallhful perforimanco of all contracts. For reference, we will furnish lhe names of numerous partics for whom we have obtalned palents during the past year. Favoras.e to Inventors.—Persons holding new inventions of machincry and imporlant improvemcnls, can have the same illustrated and explained In the Minine anp Scientiric Press, free of charge, if in our judginent Ihe discovery is one of real merit, and of sufficient interest to our readers to warrant publication. WVIll be Discontinued.—After this date subscriptions not paid for in advance will be diseontinnued. As soon as possible bills wilt be prescnicd for all arrearages. Parties who rcecive a paper from the office of delivery cannot evade the Law requiring payment for the saine. We shallin fulure keep no continned accounts with subacribers, aud the subscriptions of aut fricnds and patrons will be treated aliko. San Francisco: Saturday Morning, March 12, 1864, EARTHQUAKES. Earthquakes are a complex phenomenon, referable toa diversity of causes. ‘Their occurreuce in a given region may no doubt be attributed to a special, local cause, entirely differing from the cause which may produce similar effects in another region. Again, various causes may act conjointly, or uuder various mutual modificatious. The phenomena of earthquakes have been made a matter of much investigation, and long contiuued and close observation. Great numbers of facts have been carefully noted, and well established. No single theory has yet beeu proposed which will account for all, or even the half of the facts established. When subjected to rigid investigation, all the theories yet enunciated are found to fail, at times; generally in a majority of cases, always in a large proportion. Some idea may be formed of the amount of attention which has been devoted to this class of investigation from the fact. that one important theory has been based upon the observation of more thau six zhousand days of earthquakes ! Modern appliances and facilitics are opeuing great opportunities for observatiou in this direction as, indeed, in almost every other department of scientific research. Jor instance, the Government Coast Survey has had, and probably now has self-registering tide gauges at this port (San Francisco.) San Diego and at the mouth of the Columbia river, which re. cord the rise and fall and time of tide at those several points upon a continuous sheet of paper, moved forward regularly by clock work. It was by this instrumeut that we were enabled, to announce upon this coast, the probable occurrence, in a distant quarter, of a great earthquake, weeks, if not months before it was made known, by due course of mail. It will berecollected by most of our readers that in December, 1854, Siinoda, in Japan, was visited by a terrible eartbquake, which completely emptied that harbor of its water, and left eveu ships of war upon dry land, which but a moment before had been proudly ridiug at anchor. Of course such a disturbance created an immense wave, which swept over the greater part of the Pacific ocean. It was felt in this harbor in just twelve hours and sixteeu minutes from the time the shock spent its force in the harbor of Simoda. The clock work register, above alluded to, promptly and faithfully recorded its appearance, and told our citizens, oue bright calm day, that a series of earthquake waves had visited us, recording their maximum hight as seven-tenths of a foot. That wave had traveled 4,800 miles and oeceupied half an hour in rising and falling. It was followed by several smaller ones, in quick succession. A similar record was made at San Diego. The great earthquake at Lisbou sent a wave quite across the Atlautic ocean. It was felt along the coast line of America from South Carolina on the south, to about the middle of the Labrador coast, on the north. The gradually increasing exteut of telegraphic communieation, is greatly facilitating observations with regard to the time, extent and veloeity of these wares, all of which data are of mnch importance in investigating the producing causes of these wouderful phenomena of nature. Earthquake waves are not confined to the water. They are also developed upon land, and what may appear somowhat strange to the uninitiated, they move far more rapidly through that element thau through water. An earthquake wave travels through water at the rate of about seven miles a minute; through earth at the rate of from fifteeu to fifty oreighty. Its rate in water is nearly uniform ftom the fact that that element is quite homogeneous ; while in passing through land or earth the advancing wave is oftentimes retarded by having to traverse various descriptions and strata of ground, often eucountering caverns, fisures and seams which greatly retard its velocity. Ihe more dense and homoge. neous the body the more uniform the transmission of the wave. Numerous and well attested observations prove beyond a doubt, that the undulating motion felt during‘an earthquake is a@*‘wave,” and quite simi'ar in

character to an ocean waye. We will instance several observations which are well autheuticated, and which have been employed, in the way of illustration by Sir John Hershel. We quote :— “The way, then, that we may conceive an earthquake to travel, is this:—I shall take the case which is most common, when the motion of the ground to aud fro is horizontal. J/ow far each particular spot on the surface of the ground is actually pushed from its place there is no way of ascertaining, since all the surrounding objects receive the sanie inypulse almost at the same instant of time, but there are many iadicutions that it is often several yards. In the earthquake of Cutch, trees were seen to flog the ground with their branches, which proves that thet stens niust have been jerked suddenly away for some considerable distance and snddeuly pushed back; and the same conclusiou follows from the sudden rise of the water of lakes on the side where the shock reaches them, and its fallonthe opposite side; the bed of the lake has been jerked away for a certain distance from under the water and pulled back. Now suppose a row of sixty persons, standiug a mile apart from each otber, in a straight line, in the direction in which the shock travels, at a rate we will suppose, of sixty miles per minute, aud let the gronnd below the first get a sudden and violent shove, carrying it a yard iu the direction of thenext. Since this shock will not reach the next tillafter the lapse of one second . of time, it is clear that the space between the two willbe shortened by a yard, aud the grouud—that is to say, not the mere loose soil on the surface. but the whele mass of solid rock below down to an unknown depth—compressed, or driven into a smaller space. It is this compression that carries the shock forward. The elastic force of the rocky matter, like a coiled spring, acts both ways; it drives back the first man to his old place, and shoves the second a yard nearer to the third, and soon. Instead of men place a row of small buildings, or columns, and they will tumble down in succession, the base flying forwards, and leaving the tops behind to drop on the soil on the side from which tbe shock came. ‘This is just what was seen to happen in Messina in the great Calubrian earthqnake. As the shock ran along, the houses on the Faro were seen to topple down in succession, beginning at one end and running on to the other, as if a succession of mines had been sprung. In the earth-. quake of Cutch, a sentinel standing at oue end ofa long straight line of wall, saw the wall bow forward . and recover itself, nat all at ones, but with a swell like a wave running all along it with rapidity. In this case it is evident that the earthquake wave must ae had its front oblique to the direction of the wall.” ‘The earthquakes to which we have more particularly alluded were donbtless produced by deep seated disturbances, most likely originating in the high temperature of the far interior of the earth. We so judge mainly from their great severity and wide spread effects, the shocks traversing through and beneath extensive mountain ranges and across wide oceans. <A large majority of the earthquakes recorded are of a milder type, some of which may doubtless be attributed to the same causes as above noted, but variously and more geutly developed ; while many, most likely, have their scat of disturbauce nearer the surface, and are caused by sudden chemical changes, occurring within the solid crust of the globe, without any counectiou with internal fires. This leads ug to speak more particularly, but briefly, of ; CALIFORNIA EARTHQUAKES. There are many reasons for believing that the earthquakes which are of such frequent oecurrence throughout the valleys aud Coast Rauge of Califor~ niaare produced by the minor ageucies alluded to. A notieeable faet conuected with California earthquakes is, that those felt on the coast and in the valleys seldom if ever extend to the Sierra Nevada Range. Among all the shocks which have been experienced in San Francisco since the advent of the gold seekers, we have no recollection that any one of them has been seriously felt beyond the lower foot hills; and vice versa. ‘The earthquake which was so sensibly and extensively felt throughout the Sierra Nevada, and npon both its flanks, in the summer of 1860 (we believe we are correct in the date) was but barely perceived, if at all, in Sacramento, and not at all west of that city. These circuinstances go far towards establishing the theory, we have suggested, with regard to the seat of earthquake disturbances in the valley portions of the State, and to disprove the idea that they are consequeut upon the internal fires which are supposed to have a permanent existence bnt a few miles below the earth’s surface. We do not recollect havicg seen any recorded observations, or speculations even, upon the fact, but we have beeu led to eonclude, from the geueral directions which California earthquake waves appear to take, (from N. W. to 8. HE.) and from the limited spread of the wayes in au east and west direction, that the strata connected with tho Sierra Nevada range of mountains entirely underlies, not ouly the Sacramento and San Joaquin valleys, but probably the Coast Rauge also. If such be the fact it would follow as a matter of course, that any disturbance of the strata above this underlie would have very little teudency to effect the Sierra Nevada mountains. It is a welf known fact that a certain class of earthquakes throw out their waves, in concentric circles, without any reference to the direction of opposing nountain chains, passing freely across and through them, while others move longitudinally along extensive valleys, or along the directiou of mountain ranges. ‘I'he seat of disturbance in the latter c’ass is evidently near the surface, and it is to that class that our California earthquakes undoubtedly belong. We apprehend there can be very little doubt but that the dip of the Sierra Nevada completely underlies the scat of earthquake disturbance in the Sacramento valley and Coast Range region; hence we have but little reason to fear any very serious disturbance, such as would endanger the stability of buildings, ete., which have been crected with due regard for ordinary contingences. If this hypothesis can be sustained it willafford a vast amount of relief to the more sensitive portion of our population, both in the city and at the mines. Notwithstanding the appreliensions that have been felt. in many quarters that we may yet be visited with a destructive earthquake, we believe there is