Harry's dilemma with his device continued to plague him for the rest of the school year. When summer break started he'd experimented even more with his free time. He'd made dozens of prototype devices using everything he could shape and make by himself. Wood worked up to a point but he had to carry around a pretty large stick he'd bent into a circle around itself. But after a single use it burnt out just like his clay frame, only it actually smoked and smoldered instead of falling apart. The only good news was that his updated runic sequence had worked and he could get readings from a distance now. It was roughly thirty meters, give or take a bit, which was farther than he expected to get so he'd been happy about that. Turns out that Mrs. Figg's cats actually had a little mana in them. The large black and grey one he'd scanned with the wooden hoop had registered a '3' on the light display. This led Harry back to the problem of finding a material to spell-forge and etch with runes that wouldn't burn out after a single use. He thought that stone might work but he had no way to shape stone, so that was out. With no other options available Harry was stuck with his project.
When July came around Harry was again sent to the summer day camp. He was hopeful that he could find something to work with for his project but mainly enjoyed just crafting simple things again. The blacksmith had let him help out again and Harry had used the opportunity to imbue mana into a few small plates of metal no larger than his index finger. He'd set them aside to cool without the blacksmith noticing and retrieved them later. On the second to last day of the summer day camp Harry had innocently asked the blacksmith how glass was made. The older man had grinned at the curious boy before going out back and returning with a bag of sand. The old blacksmith had tossed in a good amount of sand and some other kind of powder into a small metal bucket. The blacksmith then closed the furnace and started pumping the bellows strongly. Black smoke billowed out of the furnace chimney as the temperature inside climbed higher and higher. After some time the blacksmith had stopped pumping the bellows and let it sit and cool. After waiting a while the old blacksmith opened the furnace and used a pair of steel tongs to extract the steel bucket. The old man poured the bucket out onto a metal work table he'd cleaned off while they waited for the furnace to cool. The still soft glass spread out in a rough circle on the table. With a grin the blacksmith handed a geared up Harry a set of steel rods and told him to make the glass any shape he wanted.
Harry nodded and as he slowly shaped the cooling glass he poured some of his mana into it. Bit by bit Harry shaped the glass while pushing his mana into it. When he finished several almost lens-shaped ovals of glass were left behind. It wasn't the crystal clear glass he had in his glasses but it was clear enough to see through easily. With a grin Harry left the blacksmith's workspace with a promise that the old man would finish his glass up so that it wouldn't crack and he'd give it to Harry tomorrow. True to his word the blacksmith handed Harry ten thin glass ovals the next morning and laughed at the beaming smile on the ten year old's face. Harry returned to Privet Drive that night ecstatic with his creations. Maybe now he could get his idea working! Vernon had complained the whole way back about the camp switching its starting and ending dates from the last few years. This year the camp had taken place in the first week of July instead of the third week like it had been before. Harry had wondered about the change but hadn't asked about it, the camp was allowed to change when it ran if it wanted to he supposed.
With his small, thin metal plates and his glass ovals Harry set about making his newest prototype mana quantifier. Oddly enough Harry found that glue could pass mana through itself without breaking down. So he'd simply glued the first glass oval onto a metal plate and slowly carved the update runic sequence into the metal. This took him almost two full days as the metal didn't give way to the blade like soft clay and wood did. When he'd finally gotten the sequence carved Harry had tied the prototype onto the right arm of his glasses so that the oval lens went over the right lens of the glasses. With a deep breath Harry had walked to the top of the stairs and looked down into the living room. Both Vernon and Dudley were watching some show and hadn't noticed him. Harry directed a bit of his mana into his creation as he focused on Vernon. Stifling his gasp when a number appeared on the oval lens Harry mentally cheered at the '1' displayed on the lens. Turning to Dudley the number disappeared and Harry sent a bit of mana into his device again. The number appeared again, another '1', as he looked at his cousin. Harry quietly retreated to his room to celebrate his successful test run.
It was the next morning when Harry picked up the mail that he saw a letter addressed to him in green ink. Turning it over he noticed a wax seal and recognized the name form his mother's notebook, Hogwarts School of Witchcraft and Wizardry.