An invention that was a huge part in Egyptian history was the invention of sun clocks and water clocks. The sun clock helped them indicate the if it was noon and helped them divide the day into two parts,  with the shadows that was on  the ground. the sun clock also indicated the longest day of the year and the shortest day of the year, later, markers added around the base of the monument would indicate further time subdivisions. As for water clocks they were the oldest time keepers. they had a bowl shape with water being dropped in to indicate hours every time water dripped and once it hit a certain height in the bowl that indicated 1 hour.

When there was no obvious  illness, many Egypt doctors and priests believed that disease was caused by spiritual beings. When no-one could explain why someone had a disease, spells and potions were used to drive out the spirits. other than trying to use potions and other types if spells they used lots if surgeries. they had documents about each body parts here is an example:  "46 vessels go from the heart to every limb, if a doctor places his hand or fingers on the back of the head, hands, stomach, arms or feet then he hears the heart. The heart speaks out of every limb."

The papyrus continues:

"There are 4 vessels to his nostrils, 2 give mucus and 2 give blood; there are 4 vessels in his forehead; there are 6 vessels that lead to the arms; there are 6 vessels that lead to the feet; there are 2 vessels to his testicles (and) it is they which give semen; there are 2 vessels to the buttocks." 

The Egyptians were  aware that the year was about 365 days, and divided it into 12 months of 30 days, with five ceremonial. This calendar lost one day every four years, and they made little attempt to correct this. 

instead, they developed another calendar based around the star Sirius, which also consisted of 365 days but which included the extra quarter day. they also kept a 360 day ceremonial calendar, running with the others, and these calendars coincided every 1461 years, which was seen as a time of great celebration and the start of a new age.