25th May 1887
From: Lord Uriah Chetworth, Cornwall.
To: Archibald Jenkins, Bristol.
Archibald,
I enjoy these short sabbaticals between expeditions, where one might rest, recuperate and repair those vital equipments that support our trade. However, during these periods of rest, the next foray will often prey upon my mind. It is the allure of the unknown that drives us out into the world, but this presents to us challenges the like of which we will never before have encountered. Our next trip vexes me so, as we will not enjoy the bright sun and clear air we enjoyed on our arctic adventure but are to be pulled into the bowels of the earth. Prepare yourself for both the crush of dark, damp squalid caves and for the grand expanse of those vast cathedrals formed by jewel-encrusted caverns, for we intend to explore extensive subterranean cave systems and wish to map their course for expeditions that will surely follow.
The darkest caves hold a myriad of intrigue for a wide variety of scientific fields, from the geological investigation of those roots that anchor our familiar landmasses to the earth, to the discovery of life isolated and never before seen, to diverge in form and function from the evolved world above. All investigators may be guided by a detailed rendering of each cave complex, surveyed and mapped by our own hands. And besides, those well-resourced gentlemen of a scientific persuasion will pay a good fee for such a cartographical aid and our expeditions consume prodigious finances for which I refuse to delve into the fortunes of the family. I have three as yet unmarried sisters to consider, and so our exploits must continue to find for themselves the funds required. As ever, your ingenuity is a welcome supplement to this endeavour, and I assume that the remuneration offered to secure your continued support does not currently demand renegotiation. Be sure to inform me, otherwise.
Returning to subterranean investigation, some may even wish to detect below the exploits of man, to understand the ways of those cultures taken to troglodyte existence. As a consequence, and in collaboration with the Royal Society, we will be accompanied by fine fellows of an anthropological enthusiasm, who wish to record that evidence of human habitation that might be found beneath the earth. To this end, we require a number of novel devices to aid in our expedition into the deepest caves, the most important of which will be light to cast upon our researches. This has long been a solved problem, for a simple flaming brand, candle or oil lamp will light our way, improved upon by those developments of Davey for use in the mining of coal. However, these options present to me some concerns that I hope you can mitigate. First, the use of an open flame in the deepest and most cramped of underground compartments does provoke pause for thought. The invention of Davey frees me from many concerns regarding the transport of a naked flame into subterranean regions in which firedamp may be encountered. However, The Regulation and Inspection of Mines Act of 1860 require coal mines to have an adequate amount of ventilation, constantly produced, to dilute and render harmless noxious gases. The natural faults into which we will foray will not be accompanied by this unnatural ventilation, and therefore it may be wise to not only fear subterranean gasses but also concern ourselves with the release of toxic or suffocating gasses into the region that we hope to explore. Furthermore, our light source and our companions will compete for the same sustenance, as both breathe the surrounding air to maintain the burning vitality that sustains flame and man alike.
Might you set your inventive mind to consider how we might better light our way below?
Uriah
8th June 1887
From: Archibald Jenkins, Bristol.
To: Lord Uriah Chetworth, Cornwall.
Uriah,
My assumptions indeed turned my mind to the industry of mines prior to my arrival at the end of your correspondence. One should always seek prior art before embarking upon an inventive step, for should we not we might live in a nation of wheels reinvented, and all clamouring to be the first to patent this wondrous device. However, upon reflection, in the exertion of small spaces and cramped conditions that are not artificially ventilated perhaps the combustion required from a small lamp might result in some discomfort. In those larger underground caverns, should we encounter some wondrous city beneath the earth, to view this panorama entire might demand a vast bonfire to cast sufficient light upon this spectacle. We would surely suffocate before we take a single gasp in wonder. Hence, whilst sceptical that the solution offered by the long experience of the mining industry does not serve your needs, I will resolve to consider an alternative all the same[1].
If we light our way no longer with the combustion that has cast a path before mankind for millennia, we will find precious few alternatives. Looking to our environment for resources[2], to be sure we may find all manner of creature that we could capture in a glass and carry before us. Phosphorescent bacteria and algae might indeed cast a weak glow which we could exploit. Our only other recourse may be to turn to technologies electrical. This Century has delivered to us all manner of electrical wonders. However, to transform these marvels into a device that could be drawn into an underground cavern might pose significant practical difficulty. Perhaps some feat of prediction might allow us to discern how such technologies might evolve, to ultimately offer us the function we desire. If such a prediction we could make, then perhaps we could realise that future all the sooner. For example, a means by which we could deliver electrical light into caverns below might be offered by a generator at the surface that can deliver electrical power via cables to arc or incandescent bulbs. This is an impractical proposal for an expedition that must arrive at the cavern mouth on foot. However, we might predict the future for this technology if we observe the evolution of other technologies, and assume that the means to cast electrical light will follow a similar course. In particular, it is an observed development that technology will become more complete as it evolves[3]. In this, the lamp may at first offer only the primary function of illumination. The environment within which this early iteration operates will supply the auxiliary inputs required to make the solution function as desired. The generator above ground serves this function. Technologies become increasingly complete as they evolve. The operating part of the system that delivers the required function will ultimately be joined by a self-contained store of energy required to achieve this function. I would therefore wager that should I review the patent record, I would no doubt find recent proposals of electrical lamps that are accompanied by their own store of energy. An electrical battery would suffice, to create a complete system that may offer sufficient power to light our way below.
And as for our arrangement, I can very much confirm in the positive that the retainer with which I am rewarded for my efforts is certainly sufficient, if not downright generous, to secure my continued support of your exploits.
Archie
[1] Sometimes you have to pull on a thread just to see where it might lead.
[2] Always list the resources in the problem space.
[3] The analysis of thousands of patents allowed Genrich Alshuller to make predictions about how the practical instantiation of functions evolve as technology improves. Here we see the first technological trend. Systems become more complete.
27th June 1887
From: Lord Uriah Chetworth, Cornwall.
To: Archibald Jenkins, Bristol.
Archibald,
I must agree that the transport of an electrical generator deep into the terrain to act as power source for a network of lights installed beneath the earth is an impractical course. The evolution of such a system to an electrical lamp with a self-contained power supply would be ideal. However, even if such advanced technology became available, I doubt that such electrical stores would sustain our lamps for the many hours, or perhaps days, that we may remain below. Does your prescience on the evolution of technologies extend sufficiently into the future to predict how the weakness of such electrical stores may become improved?
As ever, as you have long taught me, I search for resources in the problem and discover the only source of energy available in the barren subterranean spaces is to be found in the vitality of man himself. If we held man and machine together in our mind’s eye as a system complete, would this combination evolve to become better at conducting energy throughout this system[4]? If so, how might we link the glowing vitality of man to the stored power of an electrical battery?
I imagine that our hypothetical electrical generator is made to turn by the energy of petroleum. Alternatively, steam may be raised by wood fuel and water gathered from the local environment. These means of raising energy to turn a generator are large and heavy, precluding their carriage into the earth below. However, if man himself could motivate this generator to turn, would this electrical generation device be shed of sufficient weight to become portable? If so, this generator might be brought below, to periodically permit the recharge of our self contained electrical power supply once each has become exhausted.
However, this evolution is not entirely to my satisfaction. It is my opinion that an exploration into the unknown should be accompanied by equipment that provoke an agility to permit a change of plan should the situation demand. It confers no shame to an expedition, should the need arise, to retreat with all the haste demanded by the situation. Not every peoples that I have encountered on my travels have been quite as welcoming as I would desire, nor have my own ambassadorial efforts always resulted in success. So, the ability to beat a hasty withdrawal can become an unwelcome, but necessary, demand. Who knows what creatures or cultures we may encounter below the earth, so we must remain light on our feet throughout.
I would not expect that to drag a generator that could be turned by hand would achieve nought else but offer an enormous encumbrance to our progress. If the evolution of such a generator could be driven to shrink, as the mighty dinosaurs evolved from gigantic reptiles into the very starling that might perch upon my finger, I propose that the benefactor of this illumination might himself turn this generator. Under this evolution, the light is required by each speleologist is not offered by a single source of regeneration, but each below must recharge his store of electrical power for himself[5].
Uriah
[4] The second technological trend identified by Altshuller. Systems become better at conducting energy. As solutions evolve, they become more conductive to the flow of energy or information. It becomes better at distributing the flow of energy or information to each functioning part of the system.
[5] The seventh technical evolution identified by Altshuller involves the shrinking of system components and the segmentation of the system into smaller, separate parts. This evolution breaks the system into multiple copies of the same function.
18th February 1883
Newspaper: Bristol Gazzette.
Chetworth provokes international incident! It is unusual to report anything but glowing praise for the renowned Chetworh and his adventurous exploits. However, as did Icarus fly too close to the sun to his cost, Chetworth’s own ventures into the unknown can draw him close to disaster. Reports from his recent mission to Tibet suggest that the team had cause to beat a hasty retreat from an audience with the Dalai Lama himself.
Chetworth engaged in an ambassadorial mission at the behest of Her Majesty's government. The expedition ascended onto the Tibetan Plateau with Chetworth afforded all of the respect deserving as an ambassador for her Highness Queen Victoria, and as a result, was ultimately received by the Dalai Lama. A tour of the Potala Palace was arranged, a residence that has served as the winter retreat of the Dalai Lama since the 7th century. Chetworth was particularly fascinated with the ancient practice of the traditional prayer wheel, in which a mantra is written in the Tibetan language on the outside of the wheel. Spinning such a wheel will have much the same meritorious effect as orally reciting the prayers. In fluent Tibetan, Chetworth was heard to praise the Dalai Lama for the mechanical efficiency of this worship. Prayer wheels have been used in Tibet and China since the fourth century, and for centuries prayer wheels have been used to accumulate wisdom, merit and purity. Eyewitnesses report that Chetworth spent some time examining the operation of these devotional contraptions.
Some days earlier, on the arduous journey up onto the Tibetan Plateau, Chetworth had discovered a gift for the Dalai Lama amongst the wagon train, packed into crates and boxes by the gentlemen of the British foreign office. The British nation had gifted to His Holiness a newfangled automobile complete of British design and manufacture. Upon arriving at the Potala Palace and under instruction from government authorities Chetworth and his companions rebuilt this automobile and, in elaborate ceremony, presented this gift to the Dalai Lama. Witnesses report an uncomfortable silence that descended upon guests and host alike. The monks of the palace live a life of quiet contemplation with little need for automotive transport. Furthermore, the mountainous terrain of the Tibetan Plateaux affords little opportunity to employ any automobile.
Determined to fulfil the intentions of his government sponsors and keen to impress, Chetworth set himself to the task of deriving some value to the monks from the gift offered by Her Majesty. Ever resourceful, inventive and with a keen eye for efficiency, Chetworth surmised that a greater rate of rotation applied to the Tibetan prayer wheel would gather for the monks even greater wisdom, merit and purity derived from the mechanisation of our own industrious nation.
Upon a second presentation of Chetworth’s now modified automobile to His Holiness, in which the internal combustion engine was coupled to a vast array of prayer wheels, the troubles began. The enormous centrifugal pressures that arose from the prodigious rotation that Chetworth’s contraption provoked tore the prayer wheels asunder, the report of which could be perceived some valleys away. All but his serene holiness scattered from the detonation of wood and prayer, and even Chetworth himself was seen to flinch but a little. Once the dust and wood splinters had settled, the echo of this mechanical failure had died amongst the mountains, and the commotion subsided, thoughts of retribution seemed to form in the usually placid and peaceful minds of the assembled monks. Religious gentlemen of the orient are known for their expertise in the martial arts, and despite Chetworth’s renown as a champion boxer he with his companions elected to make a hasty retreat from the palace, and from the country of Tibet itself.
All was not lost, for in their retreat, unencumbered by wagon train or equipment, the expeditionary team recorded the fastest descent from the Red Mountain in living memory. Furthermore, communication from the Potala Palace to Her Majesty Queen Victoria confirmed that the whole adventure was reported by the Dalai Lama as the most amusing event he has ever witnessed in all of his many lifetimes. A subsequent return by Chetworth to the palace this very year as yet reports not repeat of such incidents.
Plate 1: ‘…reported by the Dalai Lama as the most amusing event he has ever witnessed in all of his many lifetimes.’
3rd July 1887
From: Archibald Jenkins, Bristol.
To: Lord Uriah Chetworth, Cornwall.
Uriah,
Indeed, you have correctly predicted those transformations typically observed in the evolution of technologies, and with this suggest that the coordination of energy flow between man and machine be realised by the use of a hand-operated dynamo. With this, as the charge of our electrical storage ebbs, we might stop for a while to recharge our light source with our own vitality. In effect, our lamps are supplied with energy drawn from our sustenance, and in this, for as long as we eat, we see, thus our way will be lit for hours or even days beneath the earth.
However, the practical utility of these batteries may present to us some difficulty. Not only do these storage devices present a considerable encumbrance, but also they contain hazardous materials in liquid form. I desire not to find myself in the path this electrolyte should it spill forth, as the acids required for the storage of electrical power may severely burn those in its path. Immobilised in the cramped spaces of a journey through subterranean caverns, it may prove impossible to extract oneself from the advance of such a scalding threat. I would predict that these electrical storage devices become more ideal as they evolve[6] and as a result, the harm that these liquid acids present will be trimmed. Whilst bulb and lens ever improve, these corrosive liquids seem the primary need that retards the evolution of these electrical stores[7]. Perhaps these electrolytes will become solid, or perhaps a paste, and I recommend that the gentlemen of the House manufactory embark upon a search for such chemistries. In the meantime, we should search for an alternative means to power our illumination.
To this end, your instinct to make the system more conductive to the flow of energy is correct. However, I note that in your solution you have enabled the flow of energy from man to illumination possible, but in doing so have added an additional step to this transformation. From man, to dynamo, to battery storage, to lamp. Could we increase the conductivity of energy by removing any stages in this transformation of energies? After all, the fewer steps that this energy must take, the less exhausted it will be once it reaches that destination where it might offer to us some practical service.
I propose that in consideration of the many harms observed, you remove the battery supply from this chain of events. As a consequence, the flow of vitality begins with man, then through the mechanical motion of a dynamo machine, and then directly to the source of illumination. With a step removed, the flow of energy is increased and the system becomes more conductive to this vitality, much as reducing the thickness of a pane of glass might ease the passage of light. In this, the system becomes more complete, and yet to achieve this more complete result we remove a component. Such is the somewhat counterintuitive progress of inventive thinking and a most gratifying outcome at that. I enclose an illustration of the idea proposed. A lamp is fixed firmly to a dynamo, which is affixed to the operator with a strong belt. I expect that this strap might hold the lamp in place upon the hip as the mechanism is powered, allowing operation with a single hand. However, this does not permit the direction of the illumination onto the scene of interest. To this end, I add another handle which the operator would grasp firmly to direct the light upon the object to be observed.
Archie
Plate 2: Jenkins removes the electrical battery altogether, to propose a hand-operated dynamo.
[6] The fourth technological trend. The benefits that a system offers will increase in performance or increase in number, whilst costs and harms will reduce. The ultimate outcome of this evolution towards the ideal is a system that exhibits only benefits, with all costs and harms trimmed from the solution.
[7] The fifth technological trend. Subsystems of a solution do not necessarily all evolve at the same rate. Eventually, subsystems may evolve so far apart that contradictions arise between system components.
14th July 1887
From: Lord Uriah Chetworth, Cornwall.
To: Archibald Jenkins, Bristol.
Archibald,
It is always a pleasure to spectate your efforts to trim the excess from an idea. However, you have also long warned me about the inadvertent introduction of new harms that may result when a new benefit is offered[8]. On this occasion, I fear that your inexperience with subterranean exploration has inadvertently introduced a new harm of which you are unaware. The lamp in your proposal is entirely dependent upon the constant vitality that can be offered by those who desire illumination and to this end, the explorer must continue to wind the handle to sustain this light. Furthermore, the hand unoccupied with the supply of energy to the lamp is occupied in the direction of this lamp towards the scene to be lit. Whilst we explore below, a gentleman will require considerable use of the hands to climb and clamber through the rough terrain, whilst also exercising those equipments required to make good on our commitment to survey the labyrinth below.
Perhaps the device may be operated with a single hand, to both wind the device whilst directing it to the scene. In this, the other hand may be free to operate navigation equipment. By way of experiment, I stood in the middle of the house library and imagined the operation of your dynamo-lamp. In my right hand, I grasped a fat fountain pen as if the handle of the illustrated dynamo, and turned an imagined handle to power an imagined beam of light. Whilst I wound this barrel organ on my right hip and swept the beam across the bookshelves, I reached for my fob watch with the intention of flipping the cover open to read the time as if I might scrutinise my compass to navigate the depths. The effort to operate my watch whilst winding an imagined handle rather reminded me of the game played with my sisters when but a boy, in which one might attempt to simultaneously rub one’s stomach whilst patting one’s head. A tricky operation that I expect only to be confounded by the trials of a subterranean adventure. I propose that the hand which operates the lamp must at the very least be permitted to become stationary for a moment, lest limbs degenerate into a muddle.
I very much appreciate the impractical nature of an electrical storage battery. However, our illumination will require some means to store energy which can be delivered to our illumination without constant recourse to the audience for this projector lamp. Whilst I considered this problem, it dawned upon me, standing there in the library whilst I delivered power to an imaginary mechanism, that the solution to our problem lay there in the palm of my hand. The clockwork mechanism of my fob watch, scaled up to a suitable size, might be wound by the operator on occasion, with the unwinding of a strong spring to exercise our dynamo and light our lamp. Granted, I have added back into our flow of energy a new step, very much contrary to your proposal. However, your effort is not unappreciated, for your removal of the electrical battery gave me to room to incorporate a more practical alternative into this chain of events. Hence the evolution of idea increases in benefit, whilst ejecting harms[9]. As you remove components to add utility, I step backwards in evolution to offer benefit[10]. The electrical field may be considered more advanced than mechanical, and yet the clockwork device offers us greater practical utility.
Uriah
[8] When you have a great idea, one should always begin a search for new Benefit Induced Harms.
[9] The fourth technological trend. The benefits that a system offers will increase in performance or increase in number, whilst costs and harms will reduce
[10] The eight technological trend, but reversed. The functional field will evolve to a more complex form. Functions evolve from gravitational to mechanical fields, to acoustic fields, then be replaced by thermal fields, to chemical fields which are ultimately replaced by electrical or electromagnetic effects.
6th August 1887
From: Archibald Jenkins, Bristol.
To: Lord Uriah Chetworth, Cornwall.
Uriah,
Once more my inexperience has led me astray, to be reminded of that clear motivation to always query those with experience in the assembly of those benefits desired. Indeed it is true that if we wait for sufficient time, the gradual evolution of technologies will deliver to us the functions that we desire. However, no such patience will we endure, and so to wind the evolutionary clock forwards we must propose an inventive step. In this, you wind the evolutionary clock backwards from electrical to mechanical fields, to propose a clockwork mechanism powered by a strong spring. This will demand the tension of a very powerful spring. As ever, we turn to prior art to find a suitable mechanism to wind this spring, and very rapidly we are reminded of those powerful crossbows operated by men of yore. The scrap appended to the enclosed papers is torn from a book on medieval arms that I much enjoyed in my youth. I fear my mother would be most displeased should she discover that I have torn an illustration from this text for your perusal. A foot is placed upon a stirrup to secure the device, and hand-operated cranks are employed to drive energy into the spring.
In this, the whole body can be set to work energy into the system, with both hands employed in the storage of energy. However, this is but a momentary occupation of the limbs, for once wound the delivery of stored power by spring to our illumination can commence. Hence, the lamp can be lifted before us to light our way. In the enclosed papers I illustrate the operation of this device, with only a single hand required to transport and to direct the lamp upon those scenes that we wish to illuminate. It is a recognised evolution of technologies that they progress towards a more ideal state[11]. To this end, the occupation of the hands will diminish from one to zero. In the aforementioned illustration, the operator looks towards an object of interest, and the direction of the lamp is modified by the occupied hand to illuminate the scene. Further evolution of technologies observes that those functions that rely upon one another to realise their desired ends, such as observation and illumination, become better coordinated[12]. We, therefore, expect that the motion of the head that views the scene and the motion of the hand that holds the lamp become better coordinated in their direction. Better coordination might be achieved if the lamp is not by supporting with the hand, but by the head itself. I have illustrated the power generation mechanism fixed firmly to the lamp. As a consequence, the mechanism entire must be moved to direct the illumination. To fix this combined object to the head, lamp and dynamo and spring, might snap the very neck of the operator.
If we also recognise that systems evolve to become more dynamic need the power generation move in concert with the lamp[13]? To dislocate one from the other, to allow the lamp to move independently from the dynamo, then the lamp will be more easily aimed. As a consequence might the lamp always be directed towards the object observed, and hence be incorporated into the structure of a hat? I illustrate this dislocated option in the attached papers in which the spring and dynamo can deliver their energies to a lamp mounted into a hat via a flexible cable of sufficient conductivity to deliver energy from one to the other.
Archie
Plate 3: The winding mechanism of medieval weaponry is discovered to offer a suitable means to tension a powerful spring.
Plate 4: Dynamism permits component parts to move relative to one another.
[11] The fourth technological trend. The benefits that a system offers will increase in performance or increase in number, whilst costs and harms will reduce. The ultimate outcome of this evolution towards the ideal is a system that exhibits only benefits, with all costs and harms trimmed from the solution.
[12] The third technological trend. Coordination between functions improves
[13] The technological trend 6a. Dynamism. Systems An increased ability to change parameters in time is observed. Functions become dynamic. Component parts to move relative to one another. Degrees of freedom increase.
27th August 1887
From: Lord Uriah Chetworth, Cornwall.
To: Archibald Jenkins, Bristol.
Archibald,
Prior to our journey beneath the earth, we have engaged in a preliminary expedition from which we return with a treasure. Your illustration well documents a device that will illuminate our path indefinitely, to be recharged as required, but does not occupy the hands when benefit is demanded.
With such a device in our possession, my intuition will always turn to some alternate context with which to apply the strategy you illustrate. However, on this occasion, I had no need. Harriet, my elder sister of who you are acquainted, has briefly returned from one of her many missions, overseas. Her nursing efforts do exhaust her so, and those occasional sprains she may sustain out in those field hospitals do require some rest and recuperation. I must say, I am not convinced that those who sponsor this vital overseas work take sufficient care to ensure that no injury comes to these brave girls. As head of this household, I have often threatened to make some objection in writing, and yet Harriet will always succeed in diverting me from this course.
Harriet took note of your illustrations upon my study desk and was quite intrigued by their operation. She states an explicit need to on occasion deploy in short order some illumination when engaged in her work. However, such a device must be much smaller, to offer a more portable device to her feminine frame. A review of those technologies operated by clockwork mechanism might suggest an evolution that drives towards the small scales[14]. As a result, a timepiece that once graced a grand hallway diminishes sufficiently to fit into the pocket of my waistcoat. Upon such consideration, a question arises. If technologies tend to the smaller scales, might our spring-powered illumination shrink to the size of my pocket watch? If this future is realised, then might this lamp in miniature and my watch share the mechanism to which both would turn for power?[15]. Under these circumstances, for the short time that one may wish to determine the time in a darkened environment, a clutch may engage a miniature dynamo machine conjoined to the pocket watch, to power a small lamp affixed to the lapel, separate to the power supply as is the illuminated hat of your illustration.
Harriet is delighted at the idea of this temporary electrical illumination and has requested that we might consider other portable functions that demand electrical power[16]. For example, Harriet suggests that this lamp may serve to illuminate a pocket navigational compass, or perhaps with a lens integrated project this light to allow the exploration of darkened spaces or, ever conscious of her own safety overseas, direct the aim of a pistol.
I appreciate that prior to any practical instantiation our proposal must be regarded as an enquiry, not as a resolution. And to this end, we must await the efforts and the verdict of those practical gentlemen of the House manufactory before we claim victory over the problem of subterranean darkness. All the same, congratulations my dear friend. A discovery indeed. If you would be so kind, I would very much appreciate some drawings of this ‘illuminated watch’ with which I might direct the gentlemen of the House manufactory in their efforts to construct a working prototype. Find enclosed a small token of my appreciation and for your trouble, with which you might entertain your Mother in one of the fine dining establishments of Bristol.
I look forward to your illustrations.
Uriah
Plate 5: Chetworth switches the context to find a potentially lucrative product line.
[14] The seventh technical evolution. System components shrink and segment into smaller, separate parts.
[15] The sixth technical evolution. Subsystems that compete for resources will integrate to share these resources.
[16] A second interpretation of the six technical evolution. Integrated components become able to support multiple functions. The transition from mono-systems to bi-systems to poly-systems becomes a supersystem in its own right
Historical context
This exposition of those predictable technical evolutions observed in the patent database relies upon the nascent electrical industry of the 19th Century. Our adventurers would not have to wait long for a practical torch to become available, as the first dry cell battery was invented in 1887. Unlike previous batteries, it used a paste electrolyte instead of a liquid. This was the first battery suitable for portable electrical devices, as it did not spill or break easily and worked in any orientation. The partners must wait nearly ten more years before the first mass-produced dry cell batteries become available. The first mass-produced dry cell batteries became available in 1896, and the invention of portable electric lights soon followed. In 1899 David Misellof of Great Britain was granted US617592, Electric Device. This handheld torch was powered by "D" batteries laid front to back in a paper tube with the light bulb and a brass reflector at the end. This device, now familiar in the present day, is illustrated in Figure 1.
Figure 1: The familiar electrical torch was patented in 1899.
As a consequence, at the time of the fictional correspondence between Chetworth and Jenkins, they must find some alternative means to store the power that they require to illuminate their lamps. There are many battery-powered portable electric lamps to choose from in the patent record. However, the conclusions to which Chetworth and Jenkins reach are provoked solely by patent US252691, Combined Electric Lamp And Generator, granted to Elizabeth Morey of New York in 1882 and illustrated in Figure 2. Morey’s own words best describe the operation of this device.
The object of this invention is to furnish a portable electric lamp for domestic and business purposes, which is directly combined with its generator, so as not to be dependent upon a central station for the current, but which may be readily carried from place to place, being about the size of a common table-lamp.
A designates the casing or stand of the lamp; C, the generator, and D its motive power. On top of the stand A is mounted the electric burner B, known as an “electric vacuum-lamp,” which furnishes the light by the incandescence of a piece of platinum or carbon interposed between the terminal wires of the electric circuit. The piece of carbon or platinum, whichever may be used, between the termini of the circuit-wires, is inclosed [sic] in a glass globe, B', which is suitably secured on top of the stand A. Vertically below the glass globe and light producer a small dynamo-electric machine or current-generator, C, is arranged inside of the stand A at its upper part. This machine consists essentially of field-magnets, which are rigidly secured to the sides of the stand A, revolving between which is the armature of the machine, connected by arms to a cylinder, C. provided with a commutator, against which current-collecting brushes bear, which brushes are connected directly with the terminal wires of the electric lamp, and are secured to posts fixed to the under side of the top of stand A. The dynamo-electric machine used may be either a “Gramme,” “Siemens,” or any other approved electric-current generator operating on the same principle as these. The vertical and centrally arranged shaft or spindle C° of the dynamo-electric machine is guided in suitable bearings, and bears on its lower extremity a small pinion spur wheel, which is one of a train of wheels in combination with a convolute spring and winding-up devices - a motive power of sufficient power to actuate the current-generator.
It will be seen from the above description that when the motor is wound up it will transmit a rapid rotary motion to the shaft of the dynamo-electric machine, thereby producing currents of electricity, which are directly conducted to the carbon arch or light giving part of the lamp. By establishing the proper relative proportions between the motor, the generator, and the lamp, a reliable compact and portable electric lamp adapted for domestic and other purposes is obtained without the use of a battery.
Figure 2: US252691, Combined Electric Lamp And Generator, 1882