We were at the 2019 Nuenen early gas and oil engine rally in the Netherlands, chatting to an Australian engine man from Sydney, when a noted Belgian engine collector excitedly invited us to view his recent purchase.

We crossed through the engine lines on the far side of the rally grounds to see his latest gem. It was a very nice Th.Gramme DC generator, with Build No. 3980 stamped on the shaft which has been dated as constructed in 1880, making it one of the earliest machines of this type known to exist. A very nice manufacturer’s brass nameplate was fitted to the main casting indicating Machine Gramme Brevette (patentee) S.G.D.G 20 Rue D’Hautpoul 20 Paris. BrevetŽ SGDG was a French type of patent that ceased to exist in 1968.

The name was a common abbreviation for “Brevete Sans Garantie Du Gouvernement (patent without government guarantees i.e. the French Government would not be responsible for anything which was manufactured). This was under a law of 1844 though dropped in 1968. This inscription appears on many varied items which were manufactured in France.

Interestingly in Belgium, a similar regulation was in place in Article 22 of the 1984 Patents Act, and as of 2019, was still in place. 

The dynamo mentioned here is a compound wound machine believed to be rated at 110 volts (DC) giving an output for 2,880 watts. It is in very original order with a fine period aged patina but, most importantly, it is complete. 

M. Zénobe–Théophile Gramme (b. 1826 in Belgium; d. 1901 in France) is today accepted as the inventor of the electric motor. In 1856, he began work in a Paris factory (Usine) which was at 52 rue St Georges, manufacturing electrical devices for the electrical industry which at this time was in its infancy. By 1869, he made the continuous current DC dynamo. In 1871, he entered into a partnership with M. Hippolyte Fontaine, also an inventor, and commenced fulltime manufacture of his dynamo. 

In 1873, a Th.Gramme dynamo was exhibited at the Vienna World’s Fair Exhibition in the Imperial Park (The Prater). It was demonstrated in full working order and amazed onlookers when shown it was fully reversible and could also be used as an electric motor. The rest is history - the world of electric motive power had arrived.

He traded under the name of Societe des Machines Magneto-Electriques Gramme, making the dynamo, armatures, and other devices, which included household lamp fittings in many ornate styles and bell call systems for houses and hotels.
In 1892, their catalogue showed at least 24 sizes of machines starting with output of 100 to 3500 watts. The price of each machine rose in proportion to the wattage and size. 

Most were belt driven as each was fitted with a pulley of the appropriate size. The larger sizes offered were 4-pole and 6-pole compound wound dynamos. Gramme used an alphabet system to denote the size of each dynamo i.e., A through to Z in their catalogues. The first machines were driven by steam stationary engines and the dynamos were closed coupled, then as the gas engine came into general use in the 1880s to 1900s. By the 1900 period, the oil engine started to come into its own, though there were still many manufacturing gas engines until well after the 1920s in some numbers. 

The firm became extremely well known and flourished both in Europe and worldwide. By the time of his passing in 1901, Zénobe–Théophile Gramme was a hugely wealthy man. This is certainly indicated by his tomb and statue in the well-known Pere La Chaise Cemetery in Paris, where many of the famous as well as the infamous in French history rest today. I will discuss this memorial in a future article, as a few years ago I visited it several times one sunny summer. 

My interest in dynamos and all things electrical, stems from the fact that I was an electrician for 53 years, starting my apprenticeship in 1962, which was of five years duration with the local power board. I was most fortunate to obtain this work and the training was, without doubt, first class. I was given the opportunity to go to a technical college in north Kent on a weekly day-release basis at one stage, covering all types of engineering including foundry.  

Just recently, I came across a very nice advertisement for a special device to grind the commutators of these dynamos which dates from 1904. The Phillips Commutator Grinder Co., Ltd offered such a unit. Their address is shown as being at St. Georges House, 6 & 8, Eastcheap, London, EC, though it is unclear if this was their manufacturing base. 

Today, a fine modern office block is on this site. They were the sole patentees and manufacturers of these grinders which were driven direct off the commutator. It was held in place by a cast iron pedestal or a clamp to the dynamo’s main frame. It had several levers rather similar to what you see on a lathe, to feed in the grinding wheel to make a cut. I would suggest great care would have to be taken to clear the copper swarf (particles) - leaving it when the dynamo is discharging current would cause a short. The Phillips advertisement shows they supplied them to The Royal Navy (Admiralty), the Royal Arsenal at Woolwich, the India Office, The Crown Agents for the Colonies, and other Government departments, as well as upwards of 30 Municipal Corporations from principle electric light installations to the largest dynamo makers in the Kingdom. I would say many of the local tramways departments also used them. 

At this time in 1904, the Royal Navy ‘ruled the waves’ and had the biggest fleet on the oceans. This was the Dreadnought battleship era and I think it is fair to say virtually every warship had one of these in their engineering tool store. It is a pity we could not send off for their Illustrated pamphlet for the exact prices today! As shown here, they were offered in two types - automatic or with hand-feed. 

Those of us who, in earlier years, had owned 1950s cars might remember they were fitted with a 12 volt dynamo which, if it stopped giving out any current, would have to be stripped down, the commutator would have to be cleaned in the lathe (taking the minimum cut just to clean it), and then it would be fitted with new carbon brushes. This also involved undercutting the mica insulating segments using a small, fine hacksaw blade and taking care not to damage the copper com. Before installing
it back into the vehicle, a short test with a battery would be handy to make sure the dynamo was in working order, otherwise it was an expensive trip to the auto electrician’s workshop
for repairs. 

When the Th.Gramme dynamos were first manufactured, braided copper wire brushes were fitted to the brass brush holders. In the larger-sized machines, These brushes were  fitted side by side on the bigger machines on the commutator on the bigger output of Dynamos, see illustration on the next page. They had to be adjusted frequently for wear by the skilled electrician, and a spring balance was also necessary to ensure all brush holders were set at the same tension on the commutator. 

Otherwise burning of the commutator would occur quickly and current output would be lost. 

I well remember when I was a maintenance electrician at the famous printing works of Eyre and Spottiswood Ltd, official printers to Her Majesty the Queen here in my home town of Margate in the 1970s, and I was removing a large slip ring three phase motor from underneath a German Heidelberg letter press. It was a difficult job as it was in the bowels of the machine - it was giving trouble, not answering to the speed controller and hunting, thereby giving variable speeds. The engineer and myself got it out, took it to the workshop and stripped the armature out of the casing. We found the slip rings needed attention and the brass rings were damaged. We chucked it up in the big lathe and lightly machined these rings. As well at this point, new carbon brushes were fitted, together with the set in the rotary speed controller. The motor was refitted and tested on a full run under load - all were fine. 

Printing presses must run at a constant controlled speed otherwise it affects the quality of the print. The reason why the Phillips Commutator Company of London produced this grinding device was because these copper coms were very soft. Using a steel lathe tool at this time caused much smearing which created extra work to remove the copper, especially between the slots. Therefore, grinding was a superior option using a very slow speed to obtain fine, smooth results before carefully undercutting the mica slots. It is known this grinding device was exhibited at a London engineering exhibition in 1908.

One of the directors of this company was Sydney William Goosey who was a very noted engineer, with a long life in mechanical engineering in many fields before passing away in 1940. 

I am fortunate to own a 1900 (or thereabouts) small Thomson overtype dynamo in very original order for some years. Its commutator is badly worn so it will require some restoration work in due course before it is set to my L. Gardner and Sons hot tube engine
of 1907. 

Pre-1900 and later, there were many makers of dynamos, amongst them Fabius Henrion, Nancy, France, Schneider et Cie of Le Creusot, who were one of the biggest armaments manufacturers in France; Laurence Scott & Co. Ltd, Norwich, Norfolk, UK;  Mather and Platt Ltd, Manchester, UK; and Crompton and Co. Ltd, Chelmsford, UK, makers of dynamos and alternators, to mention a few. The famous German engineering concern, Siemens, are still in the business of manufacturing generating plant unlike the aforementioned electrical companies who are now lost in the electrical mists of time.

The Phillips Commutator advertisement is from one of the fully illustrated weekly journals, The Electrical Review, published at Ludgate Hill, London, in 1904. It covered a vast array of topics of the latest innovations in electrical engineering, and is still published today. 

Acknowledgements and many thanks to Rik Lemmens, Roland Servais, and Roger Walton for sharing their knowledge with me. Also a mention of the large historical book Modern Power Generators Vol 2, by the Gresham Publishing Company, 34 Southampton Street, Strand, London, UK. Volumes one and two have many diagrams and pictorial illustrations and a series of composite sectional models which open out, of early car engines, steam stationary engines, gas engines, and electrical apparatus of all kinds. Published in February about 1908. Previously, published in France under the title Mecanicien Moderne and was widely read.

*Tim Keenan