[LB012023], Letter from Richard Nott Dyer to Thomas John Handford, April 3rd, 1882


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[LB012023], Letter from Richard Nott Dyer to Thomas John Handford, April 3rd, 1882

Editor's Notes

With reference more especially to your letter of March 14th 83 I wish to make the following comments.##Case 44##I have noted your change in the language of the description. The claim I do not like for the following reason. The end bars D which form a part of the inactive portion of the armature bobbin, are not necessarily of greater cross sectional area or lower resistance per unit of length, than the active bars B. In fact they are shown of about the same cross section. I am inclined to think that a claim something like my second claim, even if more specific, would be a better claim. I understand that bars of the same size through out in place of wire have been used. The wide plates are the distinctive feature. In view of this fact, I am inclined to favor something like this.##In a dynamo or magneto electric machine, or electric engine of the type herein before referred to, constructing the interior portions of the bobbin of wide plates having greater cross sectional area and lower resistance than the [active] bars, substantially as hereinbefore described.##Case 45##In this case I will furnish an additinal drawing showing the motors as described at the bottom of page 2 of the complete, and a complete description of the same as well as of the operation of the mechanism already described## I think your claim a good one: but it strikes me that a specific claim to the arrangements shown in the drawings *including the additional illustrations which I shall forward) would be a good claim.##2d The arrangements of parts as hereinbefore described with reference to the drawings.##Cases 45 and 46##This form of claim brings forward a point of practice. Hee a specific claim can be drawn for one thing only. But I have noticed that many English Patents have claims of this character covering each a number of arrangements show in separate figures. How are such Claims considered in English practice? I notice that in case 46 you advise the omission of claims two and five which are of this character.##Case 46.##I will forward later on descriptions of the operation with reference to the drawings, which you can use with such modifications as you see fit to make. In the preparation of future cases, I will take care to vary in that respect from our usual practice here. Claims 2 and 5 being for specific features I can see no objection to leaving them out if you consider that the better practice.##Generally with reference to examinations of English Patents already granted, my examinations are necessarily incomplete, for the reason that our set of patents has been formed incomplete on a number of occasions. they are also at present in bulk unclassified - All electrical patents being mixed together. You can safely limit your examination to patents commencing with the year 1879.




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Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
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